Basics
Cryptocurrencies are digital forms of money that exist only electronically and are not controlled by any government or central bank. Instead, they are based on decentralized networks powered by blockchain technology.
The first and most well-known cryptocurrency is Bitcoin, introduced in 2009 by an anonymous developer known as Satoshi Nakamoto. Bitcoin was designed as a peer-to-peer electronic cash system, enabling users to send and receive payments without needing a bank or payment provider.
Unlike traditional currencies, Bitcoin has a limited supply of 21 million coins. This scarcity is built into the system and helps protect it from inflation. All transactions and balances are transparently recorded on the Bitcoin blockchain, which is a public ledger maintained by thousands of computers around the world.
Bitcoin is often referred to as “digital gold” because of its limited supply and decentralized nature. Other cryptocurrencies (like Ethereum or Litecoin) may have different purposes, but Bitcoin remains the most widely recognized and trusted digital asset.
A blockchain is like a public notebook that keeps a permanent record of all transactions. Instead of being stored on one central server, it is shared across thousands of computers (nodes) worldwide.
Each set of transactions is grouped into a block, and about every 10 minutes, a new block is added to the chain. This chain of blocks—hence the name blockchain—creates a secure, transparent, and unchangeable transaction history.
Before a block is added, its content must be verified. In Bitcoin, this is done through a process called proof of work. Special computers, known as miners, compete to solve a complex puzzle. The winner gets to add the next block and earns a reward in Bitcoin.
Each block contains:
- A list of recent transactions
- A reference (hash) to the previous block
- A timestamp
- A special number called a nonce
- A unique fingerprint (hash) of all the content
Because each block depends on the previous one, changing any transaction in the past would break the entire chain. This is what makes the blockchain secure and tamper-resistant.
A crypto wallet is a tool that allows you to manage and control your digital assets, like Bitcoin. It doesn’t physically “store” your bitcoins — instead, it gives you access to the private key that proves your ownership of bitcoins recorded on the blockchain.
There are two main functions of a wallet:
- Access control: It securely stores your private key (or seed phrase), which is required to authorize transactions.
- Interface: It lets you check your balance, receive coins (via your wallet address), and send transactions to others.
There are different types of wallets (see Types of Wallets), but they all serve the same basic purpose: giving you access to your coins and protecting your private key.
Info
You don’t need to “create” a wallet in the traditional sense. Every possible private key already exists — the act of creating a wallet is simply the process of selecting one key at random and keeping it secret.
It’s important to understand:
- If you lose access to your private key, your bitcoins are lost forever.
- If someone else gains access to your private key, they can take your bitcoins.
That’s why the secure handling and backup of your wallet’s private key or seed phrase is absolutely essential.
To manage and access your own cryptocurrency — for example, Bitcoin — you need a private key. This private key is the secret access to your wallet and, therefore, to your funds.
Important!
If someone else gets access to your private key, they can take control of your coins. If you lose it, your funds are permanently lost. That’s why secure generation and storage are critical!
🔐 How is a private key created?
A Bitcoin private key is simply a 256-bit number, usually generated using a strong random process. That’s 2²⁵⁶ possible combinations — an unimaginably large number. For comparison:
- The number of atoms on Earth ≈ 2¹⁶⁶
- The number of atoms in the entire Milky Way ≈ 2²³¹
→ So the chance of someone else randomly generating the same key is practically zero.
You could create a private key, in theory, by flipping a coin 256 times and assigning 1 or 0 for each toss. The result is a 256-digit binary number.
🧮 Representing a private key
Since binary code is hard to read, private keys are usually displayed in other formats:
| Format of Private Key | Description |
|---|---|
| Binary (raw) | 00010001 10001001 ... — 256 bits, not human-friendly |
| Hexadecimal | 1189FDAFA21665D6... — 64 characters using 0–9 and A–F |
| Base58Check (WIF) | 5HueCGU8rMjxEXxiPuD5BDu... — user-friendly format used by Bitcoin wallets |
| Mnemonic Seed Phrase | bag exit hip during ... — 12 or 24 English words based on BIP-39 – human friendly |
🔠 Why Base58?
Base58Check (used in WIF) is a format designed for humans:
- It removes confusing characters like
0(zero),O(capital o),I(capital i), andl(lowercase L). - That makes it easier to read and transcribe without mistakes.
The remaining 58 characters are:
123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz
This makes Base58 ideal for encoding keys and addresses in a compact, copy-safe format.
🧠 Mnemonic Seed Phrase (BIP-39)
To make backing up a private key easier and safer, the BIP-39 standard introduced mnemonic phrases:
- A private key is converted into a list of 12 or 24 simple English words.
- These words are chosen from a list of 2048 predefined words.
- Example:
bag exit hip during green twin retreat current host admit foam motion ...
This phrase can recreate the private key and thus the wallet. It must be stored securely — if someone gets access to the phrase, they own the coins.
ℹ️ Note: For simplicity, this guide typically uses the term private key when referring to the mnemonic seed phrase. Technically, the seed phrase generates a master private key and full wallet structure, but for beginners, it’s safe to think of it as “the” private key.
Every Bitcoin wallet has a public address – like an IBAN – which others can use to send you Bitcoin.
But this address isn’t chosen at random: it is mathematically derived from your private key using cryptographic operations.
Here’s a simplified overview of the process:
- Private Key – the secret number (256-bit) generated randomly.
- Public Key – calculated from the private key using elliptic curve multiplication.
- Wallet Address – derived from the public key using a sequence of hash functions (SHA-256 and RIPEMD-160), including additional steps like checksums and Base58Check encoding.
This system is based on asymmetric cryptography, meaning that while the wallet address can be calculated from the private key, it’s mathematically impossible to reverse the process and guess the private key from the address.
🧠 Note: You don’t need to understand these steps to use Bitcoin. Your wallet software does all the math for you!
🔗 Want to explore the technical process in more detail?
Check out this guide from Saylor Academy:
https://learn.saylor.org/mod/book/tool/print/index.php?id=36353
There are different types of wallets depending on how securely the private key is stored and accessed. These types are often referred to as hot, cold, and deep cold wallets.
Hot Wallets & Exchange Wallets
These are wallets connected to the internet — for example, mobile apps, browser extensions, or exchange wallets. They are user-friendly and ideal for everyday use of smaller amounts. However, because they are always online, they are more vulnerable to malware and hacking.
If you buy Bitcoin on a crypto exchange (like Binance, Kraken, Coinbase), the exchange typically holds your private key — not you. This is convenient but involves trust. The phrase “Not your keys, not your coins” reminds users that only holding the private key means true ownership.
📱 Examples: Wallet apps, desktop wallets, browser wallets, exchange accounts.
Cold Wallets / Hardware Wallets
Cold wallets store your private key offline, making them far more secure. They’re ideal for long-term storage or larger amounts of Bitcoin.
🔐 Examples: Hardware wallets (e.g. Ledger, Trezor), paper wallets
Deep Cold Wallet
This is the most secure method, where the private key is stored completely offline and rarely accessed — often even kept in physically secured locations like safes or safety deposit boxes. Ideal for inheritance or trust planning.
NOTE:
Technically, coins are never stored “inside” a wallet. What’s stored is the private key, which gives you control over the coins stored on the blockchain.
✅ Recommendation: Use hot wallets for small, daily amounts. For savings and security, move your coins to a cold wallet where you hold the private key — and make sure to have a solid backup via a Deep Cold Wallet, such as the TIP TOP WALLET. Get yours in our shop.
✅ To receive Bitcoin, you need to share your wallet address with the sender. This address is derived from your private key and acts like your “IBAN” in the Bitcoin world. You can find it in your wallet app, often displayed as both a string of letters and numbers and as a QR code.
To avoid mistakes, always use copy-paste or the QR code—typos can lead to irreversible loss of funds.
Important: Only share the wallet address, never your private key.
💸To send Bitcoin, you need:
- The recipient’s wallet address
- Enough Bitcoin to cover the amount + a small network fee
- Access to your wallet and private key
Use your wallet app to enter the recipient’s address, the amount, and confirm the transaction. Once signed and sent, the transaction is usually confirmed on the blockchain within minutes, depending on the fee you chose.
🔄 You can buy Bitcoin with euros (or other fiat currencies) through a trusted exchange. This usually requires registering with an ID and linking a payment method such as:
- Bank transfer (SEPA)
- Credit card
- Apple Pay / Google Pay
Once you’ve bought Bitcoin, make sure to withdraw it to your own wallet. Keeping coins on exchanges is risky—you don’t control the private key.
🧊 Tip: For long-term savings and security, move your coins to a cold wallet where you hold the private key.
A deep cold wallet like the TIP TOP WALLET is ideal as a secure backup solution.
You can check the balance of your wallet at any time using a blockchain explorer. These are online tools that allow you to view the current balance and all past transactions associated with a wallet address.
To do this, simply copy and paste your wallet address (never your private key!) into the search field of a trusted blockchain explorer.
For Bitcoin, popular blockchain explorers include:
Info Box
⚠️ Always verify that you are on the correct URL. Fake explorers exist and may try to steal your data.
For Ethereum (ETH), you need a different type of explorer because Ethereum uses a different blockchain technology.
Use: etherscan.io
Note: Some multi-coin wallets (e.g., hardware wallets) may show balances for multiple cryptocurrencies in one interface. But if you want to double-check on-chain, you’ll need the appropriate explorer for each blockchain.
Handling cryptocurrencies means taking full responsibility for your assets. Unlike banks, there’s no “forgot password” button for your private key. To stay safe, keep the following principles in mind:
✅ Anyone with access to your private key or seed phrase can control your coins. Never enter it online or send it to anyone — not even for “help”.
✅ Keep larger amounts of crypto offline in a cold or deep cold wallet (like the TIP TOP WALLET). Only store smaller amounts on devices that are connected to the internet.
✅ Write your seed phrase on durable material (metal recommended), and store it in a safe place. Consider multiple secure backups in different locations.
✅ Always check website URLs and email addresses. Never click on suspicious links or download unverified files. Scammers often pose as wallet providers or support staff.
✅ Keep your computer and phone free from malware and viruses. Use up-to-date antivirus software, and consider using a separate offline device for generating wallets.
✅ Only use reputable hot or cold wallets from trustworthy sources. Open-source software and widely-reviewed hardware wallets are usually more reliable.
🔐 TIP: “Not your keys, not your coins.”
If you don’t control the private key, you don’t truly control the funds — even if they appear in your app or exchange account.
Even with all precautions, things can still go wrong. Here’s what you should (and shouldn’t) do in some common situations:
❌ I lost access to my wallet app
If you still have your private key or seed phrase, you can restore access using another compatible wallet. Just import the key into a trusted hot or cold wallet.
❌ I lost my seed phrase or private key
Unfortunately, without your private key or seed phrase, your funds are lost — forever. There is no recovery option. This is why secure backups are essential.
❌ My device was hacked / compromised
Immediately move your funds to a new wallet with a new private key using a secure, uncompromised device. Then destroy the compromised wallet’s access.
❌ I sent Bitcoin to the wrong address
Transactions on the blockchain are irreversible. There is no way to undo or cancel a payment once it’s confirmed. Always double-check the address — or use QR codes.
❌ I see strange transactions from my wallet
This usually means your private key has been compromised. Act fast: create a new wallet and transfer remaining funds, if any, to a safe place.
Note:
🚨 There is no official support hotline for Bitcoin.
Be extremely careful with anyone offering help online — especially in forums or social media. Scammers often pose as “support agents”.
Advanced
Cryptocurrencies are digital forms of money that exist only electronically and are not controlled by any government or central bank. Instead, they are based on decentralized networks powered by blockchain technology.
The first and most well-known cryptocurrency is Bitcoin, introduced in 2009 by an anonymous developer known as Satoshi Nakamoto. Bitcoin was designed as a peer-to-peer electronic cash system, enabling users to send and receive payments without needing a bank or payment provider.
Unlike traditional currencies, Bitcoin has a limited supply of 21 million coins. This scarcity is built into the system and helps protect it from inflation. All transactions and balances are transparently recorded on the Bitcoin blockchain, which is a public ledger maintained by thousands of computers around the world.
Bitcoin is often referred to as “digital gold” because of its limited supply and decentralized nature. Other cryptocurrencies (like Ethereum or Litecoin) may have different purposes, but Bitcoin remains the most widely recognized and trusted digital asset.
A blockchain is like a public notebook that keeps a permanent record of all transactions. Instead of being stored on one central server, it is shared across thousands of computers (nodes) worldwide.
Each set of transactions is grouped into a block, and about every 10 minutes, a new block is added to the chain. This chain of blocks—hence the name blockchain—creates a secure, transparent, and unchangeable transaction history.
Before a block is added, its content must be verified. In Bitcoin, this is done through a process called proof of work. Special computers, known as miners, compete to solve a complex puzzle. The winner gets to add the next block and earns a reward in Bitcoin.
Each block contains:
- A list of recent transactions
- A reference (hash) to the previous block
- A timestamp
- A special number called a nonce
- A unique fingerprint (hash) of all the content
Because each block depends on the previous one, changing any transaction in the past would break the entire chain. This is what makes the blockchain secure and tamper-resistant.
A crypto wallet is a tool that allows you to manage and control your digital assets, like Bitcoin. It doesn’t physically “store” your bitcoins — instead, it gives you access to the private key that proves your ownership of bitcoins recorded on the blockchain.
There are two main functions of a wallet:
- Access control: It securely stores your private key (or seed phrase), which is required to authorize transactions.
- Interface: It lets you check your balance, receive coins (via your wallet address), and send transactions to others.
There are different types of wallets (see Types of Wallets), but they all serve the same basic purpose: giving you access to your coins and protecting your private key.
Info
You don’t need to “create” a wallet in the traditional sense. Every possible private key already exists — the act of creating a wallet is simply the process of selecting one key at random and keeping it secret.
It’s important to understand:
- If you lose access to your private key, your bitcoins are lost forever.
- If someone else gains access to your private key, they can take your bitcoins.
That’s why the secure handling and backup of your wallet’s private key or seed phrase is absolutely essential.
To manage and access your own cryptocurrency — for example, Bitcoin — you need a private key. This private key is the secret access to your wallet and, therefore, to your funds.
Important!
If someone else gets access to your private key, they can take control of your coins. If you lose it, your funds are permanently lost. That’s why secure generation and storage are critical!
🔐 How is a private key created?
A Bitcoin private key is simply a 256-bit number, usually generated using a strong random process. That’s 2²⁵⁶ possible combinations — an unimaginably large number. For comparison:
- The number of atoms on Earth ≈ 2¹⁶⁶
- The number of atoms in the entire Milky Way ≈ 2²³¹
→ So the chance of someone else randomly generating the same key is practically zero.
You could create a private key, in theory, by flipping a coin 256 times and assigning 1 or 0 for each toss. The result is a 256-digit binary number.
🧮 Representing a private key
Since binary code is hard to read, private keys are usually displayed in other formats:
| Format of Private Key | Description |
|---|---|
| Binary (raw) | 00010001 10001001 ... — 256 bits, not human-friendly |
| Hexadecimal | 1189FDAFA21665D6... — 64 characters using 0–9 and A–F |
| Base58Check (WIF) | 5HueCGU8rMjxEXxiPuD5BDu... — user-friendly format used by Bitcoin wallets |
| Mnemonic Seed Phrase | bag exit hip during ... — 12 or 24 English words based on BIP-39 – human friendly |
🔠 Why Base58?
Base58Check (used in WIF) is a format designed for humans:
- It removes confusing characters like
0(zero),O(capital o),I(capital i), andl(lowercase L). - That makes it easier to read and transcribe without mistakes.
The remaining 58 characters are:
123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz
This makes Base58 ideal for encoding keys and addresses in a compact, copy-safe format.
🧠 Mnemonic Seed Phrase (BIP-39)
To make backing up a private key easier and safer, the BIP-39 standard introduced mnemonic phrases:
- A private key is converted into a list of 12 or 24 simple English words.
- These words are chosen from a list of 2048 predefined words.
- Example:
bag exit hip during green twin retreat current host admit foam motion ...
This phrase can recreate the private key and thus the wallet. It must be stored securely — if someone gets access to the phrase, they own the coins.
ℹ️ Note: For simplicity, this guide typically uses the term private key when referring to the mnemonic seed phrase. Technically, the seed phrase generates a master private key and full wallet structure, but for beginners, it’s safe to think of it as “the” private key.