A cryptocurrency wallet is a software program that stores private and public keys and interacts with various blockchain to enable users to send and receive digital currency and monitor their balance. If you want to use Bitcoin or any other cryptocurrency, you will need to have a digital wallet.
Cryptocurrency wallets store secret keys used to digitally sign transactions for blockchain distributed ledgers, but their future goes far beyond being just a keeper of cryptocurrencies. They could one day represent your professional and financial status, or even your personal identity.
How Do They Work?
Millions of people use cryptocurrency wallets, but there is a considerable misunderstanding about how they work. Unlike traditional 'pocket' wallets, digital wallets don't store currency. In fact, currencies don't get stored in any single location or exist anywhere in any physical form. All that exists are records of transactions stored on the blockchain.
Cryptocurrency wallets are software programs that store your public and private keys and interface with various blockchains so users can monitor their balance, send money and conduct other operations. When a person sends you bitcoins or any other type of digital currency, they are essentially signing off ownership of the coins to your wallet's address. To be able to spend those coins and unlock the funds, the private key stored in your wallet must match the public address the currency is assigned to. If the public and private keys match, the balance in your digital wallet will increase, and the senders will decrease accordingly. There is no actual exchange of real coins. The transaction is signified merely by a transaction record on the blockchain and a change in balance in your cryptocurrency wallet.
Every Cryptocurrency Wallet Has A Public key And A Private key
Your public key is used to receive funds. It identifies your account on the network. It can be searched in the ledger.
Your private key is only used to sign transactions and prove you own the related public key. You should never share it under any circumstances.
Every cryptocurrency wallet has a public key and a private key.
To make sure you have a full understanding, I will quickly explain the role of a wallet address, as well as a private and public key, as they are all related.
As mentioned, Coins are not actually stored in a physical wallet, as cryptocurrencies do not exist in a physical form. Instead, the blockchain consists of transactional records that details which private and the public key has control over the funds.
A wallet address is like a bank account number. There is no harm in giving somebody else your bank account number, as people will need it if they are to transfer your funds. This could be so your employer can pay you your salary, so a customer can pay your invoice or so that your friends and family can send you some birthday money!
In the world of cryptocurrency, if somebody wants to transfer your coins, you simply give them your wallet address. Just like in the real world, no two wallet addresses are ever the same, which means that there is no chance that somebody else would get your funds. Also, there is no limit to the number of wallet addresses you can create.
To give you an example of what a Bitcoin address looks like, here is the wallet address that is believed to belong to the creator of Bitcoin, Satoshi Nakamoto!
As you can see, it uses a combination of numbers and letters, using both upper case and lower case. As most blockchains are transparent, it is easy to find out how much money a certain cryptocurrency wallet has, as well as the transactions the owner has previously made.
However, a cryptocurrency wallet address does not reveal the real-world identity of its owner, which is why the blockchain is referred to as "pseudonymous".
How Do Private And Public Keys Relate To A Wallet Address?
So, now that you know that a wallet address is very similar to a bank account number, I am now going to explain how you are given control of the funds. People often think that a public key is the same as a public wallet address, however, this is not correct.
Essentially, each individual cryptocurrency wallet address (remember, no two addresses can be the same) each have a unique private and public key. The private key allows you to access the funds that are related to the crypto wallet address.
To give you a real-world example, when you want to transfer money from your bank account to somebody else's bank account, you will need to enter your private password. Nobody else has access to this password, not even the bank. Otherwise, if somebody knew what it was, they would be able to send money from your bank account!
A private key does the exact same job and it is linked specifically to the individual crypto wallet address. So what about a public key? A public key is mathematically linked to your wallet address! However, it is a "hashed version", which I will explain below.
A hash function allows a sequence of letters and/or numbers (called an "input") to be encrypted into a new set of letters and/or numbers (called an "output"). This adds an extra layer of security and ensures that your wallet cannot be hacked.
The two sets of keys are completely different, to the human eye, however, the software technology knows that the two keys are specifically linked to each other! That proves that you are the owner of the coins and it allows you to transfer funds whenever you want!
The important thing to remember is that everything I have explained here is very technical. However, when you use a cryptocurrency wallet, the software does everything for you. It's like using the internet to send an email!
You don't actually need to understand the technology that runs in the background, the likes of Gmail and Hotmail do everything for you regarding emails, just like a cryptocurrency wallet does regarding crypto transactions!
As Bitcoin and other cryptocurrencies are not physical money, they are digitally stored on the blockchain. The blockchain is like a giant accounting ledger that stores every single transaction that has ever occurred in the system, as well as the total account balances of each public address.
The software within the cryptocurrency wallet is connected directly to the blockchain, so it allows you to submit transactions to the ledger. However, the crypto wallet is the protocol that generates your public and private keys. Without it, you wouldn't be able to access your funds in the real world.
To get a better understanding of this relationship, think about walking into a store and paying for goods using a debit or credit card. There is no physical exchange of money between you and the store. However, by entering your private pin number, you verify that you own the funds and so they can move the funds from your account to the account of the store.
This is the same as a cryptocurrency wallet. By entering your private key, you verify that you own the coins and then you can transfer them to someone else. That is the only way that the coins can move from person A to person B.
The Different Types Of Cryptocurrency Wallets
There are several types of wallets that provide different ways to store and access your digital currency. Wallets can be broken down into three distinct categories - software, hardware, and paper. Software wallets can be a desktop, mobile or online:
• Desktop - wallets are downloaded and installed on a PC or laptop. They are only accessible from the single computer in which they are downloaded. Desktop wallets offer one of the highest levels of security however if your computer is hacked or gets a virus there is the possibility that you may lose all your funds.
• Online - wallets run on the cloud and are accessible from any computing device in any location. While they are more convenient to access, online wallets store your private keys online and are controlled by a third party which makes them more vulnerable to hacking attacks and theft.
• Mobile - wallets run on an app on your phone and are useful because they can be used anywhere including retail stores. Mobile wallets are usually much smaller and simpler than desktop wallets because of the limited space available on mobile.
• Hardware - wallets differ from software wallets in that they store a user's private keys on a hardware device like a USB. Although hardware wallets make transactions online, they are stored offline which delivers increased security. Hardware wallets can be compatible with several web interfaces and can support different currencies; it just depends on which one you decide to use. What's more, making a transaction is easy. Users simply plug in their device to any internet-enabled computer or device, enter a pin, send currency and confirm. Hardware wallets make it possible to easily transact while also keeping your money offline and away from danger.
• Paper - wallets are easy to use and provide a very high level of security. While the term paper wallet can simply refer to a physical copy or printout of your public and private keys, it can also refer to a piece of software that is used to securely generate a pair of keys which are then printed. Using a paper wallet is relatively straightforward. Transferring Bitcoin or any other currency to your paper wallet is accomplished by the transfer of funds from your software wallet to the public address shown on your paper wallet. Alternatively, if you want to withdraw or spend currency, all you need to do is transfer funds from your paper wallet to your software wallet. This process, often referred to as 'sweeping,' can either be done manually by entering your private keys or by scanning the QR code on the paper wallet.
• Full Node Wallet - A wallet where you control your private keys and host a full copy of the blockchain. Essentially every coin has an official wallet of this type and that can be found on the official GitHub of the site (there is often a link on the official website). NOTE: "Official" in this sense means "put out by or endorsed by the developers who created the coin." Many cryptos are decentralized, so there is no real official anything.
• Custodial Wallet - Some wallets let you control your private keys, some are custodial (you don't control your keys directly). Most exchange wallets are custodial wallets.
• Software Wallet - Any wallet that is software-based is a software wallet.
• Coin-specific - A wallet that only works with a specific coin.
• Network-specific - A wallet that can hold multiple tokens on a single network.
• Universal/multi-asset/multi-coin - A wallet that can hold addresses from multiple coins. Please note that just because a wallet is "universal" doesn't mean it literally holds every crypto asset. From exchanges to the best multi-asset wallet out there, I don't know of any product that holds literally every crypto.
Are Cryptocurrency Wallets Secure?
Wallets are secure to varying degrees. The level of security depends on the type of wallet you use (desktop, mobile, online, paper, hardware) and the service provider. A web server is an intrinsically riskier environment to keep your currency compared to offline. Online wallets can expose users to possible vulnerabilities in the wallet platform which can be exploited by hackers to steal your funds. Offline wallets, on the other hand, cannot be hacked because they simply aren't connected to an online network and don't rely on a third party for security.
Although online wallets have proven the most vulnerable and prone to hacking attacks, diligent security precautions need to be implemented and followed when using any wallet. Remember that no matter which wallet you use, losing your private keys will lead you to lose your money. Similarly, if your wallet gets hacked, or you send money to a scammer, there is no way to reclaim lost currency or reverse the transaction. You must take precautions and be very careful!
Here are some examples of how a hacker could access your funds that are stored alongside an internet connection:
• Key logger.
• Remote access to your device.
There are a number of things that you can do to protect yourself from the above threats:
• Backup your wallet - Store only small amounts of currency for everyday use online, on your computer or mobile, keeping the vast majority of your funds in a high-security environment. Cold or offline storage options for backup like Ledger Nano or paper or USB will protect you against computer failures and allow you to recover your wallet should it be lost or stolen. It will not, however, protect you against eager hackers. The reality is, if you choose to use an online wallet there are inherent risks that can't always be protected against.
• Update software - Keep your software up to date so that you have the latest security enhancements available. You should regularly update not only your wallet software but also the software on your computer or mobile.
• It is also a good idea to consider a wallet that allows multi-signatures. Basically, a multi-signature wallet means that to send funds, the user must authenticate the transaction using two or more separate devices. This way, if one of your devices is lost, stolen or hacked, the criminal won't be able to access your cryptocurrency, as they would need the other device(s) too!
• Add extra security layers - The more layers of security, the better. Setting long and complex passwords and ensuring any withdrawal of funds requires a password is a start. Use wallets that have a good reputation and provide extra security layers like two-factor authentication and additional pin code requirements every time a wallet application gets opened. You may also want to consider a wallet that offers multisig transactions like Armory or Copay. A multisig or multi-signature wallet requires the permission of another user or users before a transaction can be made.
Multi-Currency Or Single-Use
Although Bitcoin is by far the most well-known and popular digital currency, hundreds of new cryptocurrencies (referred to as altcoins) have emerged, each with distinctive ecosystems and infrastructure. If you're interested in using a variety of cryptocurrencies, the good news is, you don't need to set up a separate wallet for each currency. Instead of using a cryptocurrency wallet that supports a single currency, it may be more convenient to set up a multi-currency wallet which enables you to use several currencies from the same wallet.
In general, transaction fees are a tiny fraction of traditional bank fees. Sometimes fees need to be paid for certain types of transactions to network miners as a processing fee, while some transactions don't have any fee at all. It's also possible to set your own fee. As a guide, the median transaction size of 226 bytes would result in a fee of 18,080 satoshis or $0.12. In some cases, if you choose to set a low fee, your transaction may get low priority, and you might have to wait hours or even days for the transaction to get confirmed. If you need your transaction completed and confirmed promptly, then you might need to increase the amount you're willing to pay. Whatever wallet you end up using, transaction fees are not something you should worry about. You will either pay minuscule transaction fees, choose your own fees or pay no fees at all. A definite improvement from the past!
Kind of, but not really. Wallets are pseudonymous. While wallets aren't tied to the actual identity of a user, all transactions are stored publicly and permanently on the blockchain. Your name or personal street address won't be there, but data like your wallet address could be traced to your identity in a number of ways. While there are efforts underway to make anonymity and privacy easier to achieve, there are obvious downsides to full anonymity. Check out the DarkWallet project that is looking to beef up privacy and anonymity through stealth addresses and coin mixing.
Cryptocurrency Wallets Selection
There is an ever-growing list of options. Before picking a wallet, you should, however, consider how you intend to use it:
• Do you need a wallet for everyday purchases or just buying and holding the digital currency for an investment?
• Do you plan to use several currencies or one single currency?
• Do you require access to your digital wallet from anywhere or only from home?
• Take some time to assess your requirements and then choose the most suitable wallet for you.
Atomic Wallet is a new multi-asset custody-free solution for secure storage and management of BTC, ETH, XLM, XRP, LTC, and over 300 other coins and tokens. The crypto-assets and features are regularly updated. Private keys are securely encrypted on a user's device, so one has full control over their funds. The desktop app is available for Windows, MacOS, Ubuntu, Debian and Fedora. Private alpha versions of Android and IOS mobile apps will be released in October, 2018. Atomic Wallet is a secure all-in-one, non-custodial cryptocurrency storage with a smooth and comprehensive interface. The wallet supports Atomic Swaps, a cutting-edge feature that helps users significantly save on fees. Atomic wallet also enables users to buy cryptocurrency with USD and EUR and exchange their assets at the best rates via Changelly or ShapeShift:
• Pros - Handy interface, Optimum privacy & security, Decentralized, Multi-currency.
• Cons - Not all coins support Atomic swaps yet.
Bread Wallet is a simple mobile Bitcoin digital wallet that makes sending bitcoins as easy as sending an email. The wallet can be downloaded from the App Store or Google Play. Bread Wallet offers a standalone client, so there is no server to use when sending or receiving bitcoins. That means users can access their money and are in full control of their funds at all times. Overall, Bread Wallet's clean interface, lightweight design and commitment to continually improve security, make the application safe, fast and a pleasure to use for both beginners and experienced users alike:
• Pros - Good privacy & security, beginner-friendly, simple & clean, open-source software, free.
• Cons - No web or desktop interface, lacks features, hot wallet.
Advanced users searching for a Bitcoin mobile digital wallet, should look no further than mycelium. The Mycelium mobile wallet allows iPhone and Android users to send and receive bitcoins and keep complete control over bitcoins. No third party can freeze or lose your funds! With enterprise-level security superior to most other apps and features like cold storage and encrypted PDF backups, an integrated QR-code scanner, a local trading marketplace and secure chat amongst others, you can understand why Mycelium has long been regarded as one of the best wallets on the market:
• Pros - Good privacy, advanced security, feature-rich, open-source software, free.
• Cons - No web or desktop interface, hot wallet, not for beginners.
Exodus is a relatively new and unknown digital wallet that is currently only available on the desktop. It enables the storage and trading of Bitcoin, Ether, Litecoins, Dogecoins, and Dash through an incredibly easy to use, intuitive and beautiful interface. Exodus also offers a very simple guide to backup your wallet. One of the great things about Exodus is that it has a built-in shapeshift exchange that allows users to trade altcoins for bitcoins and vice versa without leaving the wallet:
• Pros - Good privacy & security, beginner friendly, intuitive, easy to use, in-wallet trading, supports multiple currencies, open-source software, free.
• Cons - Hot wallet, no web interface or mobile app.
Created by Bitpay, Copay is one of the best digital wallets on the market. If you're looking for convenience, Copay is easily accessed through a user-friendly interface on desktop, mobile or online. One of the best things about Copay is that it's a multi-signature wallet so friends or business partners can share funds. Overall, Copay has something for everyone. It's simple enough for entry-level users but has plenty of additional geeky features that will impress more experienced players as well:
• Pros - Good privacy & security, multisig transactions, multiple platforms & devices, multiple wallet storage, beginner-friendly, open-source software, free.
• Cons - Can be slow & unresponsive, limited user support.
Enterprises have to bear a lot of loss due to chargebacks. Business owners complain that they lose a lot of money to chargebacks. A chargeback is basically a one-way scam where customers use the products and services for free by reporting fraudulent charges against the business to their credit card company. While it is not impossible to fight those charges, but it takes a lot of time and effort for the businesses that they finally decide to take up the loss:
• Pros - Good privacy & security, Multi-currency, wallet linking across multiple platforms, great user support, feature-rich, user-friendly, free.
• Cons - The code is not open source, can be slow to load.
Armory is an open-source Bitcoin desktop wallet perfect for experienced users that place emphasis on security. Some of Armory's features include cold storage, multi-signature transactions, one-time printable backups, multiple wallets interface, GPU-resistant wallet encryption, key importing, key sweeping and more. Although Armory takes a little while to understand and use to its full potential, it's a great option for more tech-savvy bitcoiners looking to keep their funds safe and secure:
• Pros - Good privacy, great security features, multi-signature options, solid cold storage options, free.
• Cons - Only accessible via the desktop client, not for beginners.
Trezor is a hardware Bitcoin wallet that is ideal for storing large amounts of bitcoins. Trezor cannot be infected by malware and never exposes your private keys which make it as safe as holding traditional paper money. Trezor is open source and transparent, with all technical decisions benefiting from wider community consultation. It's easy to use, has an intuitive interface and is Windows, OS X, and Linux friendly. One of the few downsides of the Trezor wallet is that it must be with you to send bitcoins. This, therefore, makes Trezor best for inactive savers, investors or people who want to keep large amounts of Bitcoin highly secure:
• Pros - Good security & privacy, cold storage, easy to use a web interface, in-built screen, open-source software, beginner-friendly.
• Cons - Costs $99, a must-have device to send bitcoins.
The Ledger Wallet Nano is a new hierarchical deterministic multisig hardware wallet for bitcoin users that aims to eliminate a number of attack vectors through the use of a second security layer. This tech-heavy description does not mean much to the average consumer, though, which is why I am going to explain it in plain language, describing what makes the Ledger Wallet Nano tick. In terms of hardware, the Ledger Wallet Nano is a compact USB device based on a smart card. It is roughly the size of a small flash drive, measuring 39 x 13 x 4mm (1.53 x 0.51 x 0.16in) and weighing in at just 5.9g:
• Screen/device protected by metal swivel cover.
• Multi-Currency support.
• 3rd-Party apps can run from the device.
• U2F support.
• When recovering a wallet from seed, the whole process can be done from the device without even connecting it to a computer!
• Fairly inexpensive (approx $65 USD).
• Not as advanced wallet software (no transaction labeling).
• No ability to create hidden accounts.
• No password manager.
Green Address is a user-friendly Bitcoin wallet that's an excellent choice for beginners. Green Address is accessible via desktop, online or mobile with apps available for Chrome, iOS, and Android. Features include multi-signature addresses & two-factor authentications for enhanced security, paper wallet backup, and instant transaction confirmation. A downside is that Green Address is required to approve all payments, so you do not have full control over your spending:
• Pros - Solid security, multi-platform & device, multi-sig, beginner-friendly, open-source software, free.
• Cons - Hot wallet, average privacy, the third party must approve payments.
Blockchain (dot) Info
Blockchain is one of the most popular Bitcoin wallets. Accessing this wallet can be done from any browser or smartphone. Blockchain.info provides two different additional layers. For the browser version, users can enable two-factor authentication, while mobile users can activate a pin code requirement every time the wallet application is opened. Although your wallet will be stored online and all transactions will need to go through the company's servers, Blockchain.info does not have access to your private keys. Overall, this is a well-established company that is trusted throughout the Bitcoin community and makes for a solid wallet to keep your currency:
• Pros - Good security, easy to use web & mobile interface, well-known & trusted company, beginner-friendly, free.
• Cons - Hot wallet, weak privacy, the third-party trust required, has experienced outages.
Tips On Wallets
We typically suggest using an official (or officially endorsed) wallet for any given coin. So, for Bitcoin we would suggest using the Bitcoin Core Wallet, for Litecoin we would suggest Litecoin Core, and for Ethereum we would suggest either Ethereum Wallet or MyEtherWallet.
Check the official website of a coin for official recommendations. Please note, the full wallet of a given coin will likely require a lot of hard drive space, to avoid having to deal with this, see the other options below.
Since the full official wallets of coins can require users to download very large files, and since some people tend to own a lot of coins, it is good to look at alternatives.
For those who want to use or invest in many coins, universal wallets/multi- asset wallets/multi-coin wallets are a good choice. There are software wallets that are universal like Coinomi, Exodus, Atomic Wallet, and Ethos that typically have desktop and phone app versions and hardware wallets that are universal like TREZOR and the Nano S (hardware wallets are generally good choices for long-term storage).
In choosing a wallet you'll also need to decide between a custodial and non-custodial wallet. That is, non-custodial wallets like Blockchain Wallet and MyEtherWallet where you control your private keys directly but use the wallet as an interface, and custodial wallets where you don't control your private keys directly like Coinbase (although people are advised against keeping all their funds on an exchange, exchanges like Binance generally double as custodial wallets as well).
You should also be aware there are wallets designed for specific networks and their functionalities. For example, other features aside, Coinbase Wallet (a Coinbase product) and Trust double as Ethereum-based wallets that let you store a range of Ethereum-based tokens and also act as web browsers for the decentralized web (they allow you to interface with DApps).
In simple terms, which wallet you choose depends on your needs. Generally speaking non-custodial offline wallets like TREZOR are great for long term storage, custodial wallets like Binance are essentially mandatory for trading, and a software wallet that you can use as an app like Coinbase, Blockchain Wallet, and Trust are solid choices for every day use. If you stick to the big names and use best practices, it is hard to go wrong and a lot boils down to choice.
There is overlap between the above wallet types, for example Coinbase Wallet is a semi-custodial multi-asset software wallet with an ethereum web browser. Multi-asset wallets are also called multi-coin wallets. The reason asset is used instead of coin above is because not all crypto tokens that can be stored in wallets are meant to be used as currencies.
There is no one single wallet that stores every coin. So you'll need to figure out which wallets you need based on which coins you want to invest in or use (or vice versa).
You can store all ERC-20 tokens (tokens created on the Ethereum platform AKA Ethereum-based tokens) in an ERC-20 friendly wallet like MyEtherWallet, Trust, or Coinbase Wallet. Many Ethereum-based tokens also have their own wallets as well (check the coin's official Github or website for official wallets). If you are investing an an ICO, you'll likely need an ERC-20 friendly wallet to store/send tokens.
A full node wallet that downloads the full blockchain of a coin is called a "full node." These wallets can take up a lot of space and use a good bit of energy since they need to download the entire blockchain and keep it updated. Bitcoin Core, Litecoin Core, and Ethereum Wallet are examples of full node wallets. If you don't have a lot of disk space free to commit to running a node, consider one of the other wallet options instead.
Watch out for browser extension malware if you are using online wallets, you may want to use a different browser for your online wallet than you do for your day-to-day internet browsing.
The term "hot wallet" describes a wallet connected to the internet. The term "cold wallet" describes a wallet not connected to the internet (for example a hardware wallet unplugged and in a safe.) When cryptocurrency is in "cold storage" that means it is being held offline in a "cold wallet." Funds you want to use like cash should be in hot wallets, funds you want to store long term are best held in "cold storage" in an offline wallet. Hot wallets are considered "hot targets" (i.e., they are targets for hackers). Thus, if you have a "hot wallet," make sure you have as many layers of protection on it as you can (two factor, strong password, all security settings on, etc).
IMPORTANT: Remember that with any non-custodial wallet, if you lose your private key, then you lose your money. That is true for paper wallets, hardware wallets, or any other wallet type. The reason you lose your keys doesn't matter; there is no way to reclaim your cryptocurrency without them. Further, if your wallet is hacked, be it with a custodian or not, and your funds are taken, then you lose your money. It is not always fun, but it is the way it is. So make sure to use best practices and keep your wallets secure.
With the above in mind, if you are new to cryptocurrency, we suggest doing one or more of the following:
1. Download the official (or officially endorsed) wallet from the official website.
2. Sign up for a custodial wallet service like Coinbase or non-custodial wallet service like Blockchain Wallet (which handles a wallet and exchange with one account).
3. Purchase a hardware wallet like TREZOR for long term storage.
4. And/or, use a universal software wallet or other wallet that suits your needs like the ones noted above (for example, Trust for exploring the Ethereum ecosystem or Atomic Wallet for holding a swapping a range of coins).
Of the above Coinbase and TREZOR are good choices, since they don't require a lot of technical know how, have guides, can be kept safe with best practices, and don't require you to download the full blockchain fo a coin.
If you know what you are doing, there are a wide range of different wallets to choose from, as mentioned above, which offer different pros and cons.
Cryptocurrency wallets are all built to be secure, but the exact security differs from wallet to wallet. Generally, like your usernames and passwords, the security of your wallet comes from you using best practices. We suggest not keeping more currency than you need at one time in a single wallet that you use frequently, using google authenticator for extra layers of protection, encrypting your wallet, and using an official (or officially endorsed wallet). You can also use multi-signature transactions.
It's smart to backup your wallet and private keys and to encrypt them. At least one backup should be on a CD or thumb drive to ensure that you have a "hard copy" laying around. If you lose your wallet or your keys, then you lose the currency connected to it!
Some software offered as a wallet is malware trying to take advantage of those willing to download and install unofficial software off the internet. Never trust mining or wallet software that comes from a source that you don't know and trust. Start with well worn solutions like the ones explained above, then move onto other wallets after you know what you are doing.
Always use a strong password and all available security measures. For example, if you can use two-factor, then use two-factor (for example Google Authenticator)!
Never share your wallet password, seed, PIN, or private key and make sure to store them somewhere safe (and ideally offline). To send coins and receive coins you only need to share your public wallet address (your "public key").
Always access your wallet offline when you can. And never enter your password, seed, or private key anywhere other than your wallet or the secure place you are storing your password.
As a rule of thumb don't keep more currency in your digital wallet than you would in your real one!
If you use Coinbase, consider using their vault service to add an extra layer of protection to coins you aren't actively trading or using.