¶ What is a blockchain?
A blockchain is a decentralized digital ledger that records transactions across a network of computers.
It is called "blockchain" because the transactions are organized into blocks, which are linked and secured using cryptography.
Once a block is added to the blockchain, the information it contains is considered to be permanent and unalterable. This makes blockchains highly secure and resistant to fraud and tampering.
Because blockchains are decentralized and transparent, they offer a way to store and transfer information and assets in a way that is secure and trustworthy, without the need for a central authority or intermediary.
¶ What are special features of the Cardano blockchain?
¶ The Cardano blockchain has several unique features that distinguish it from other blockchain platforms:
¶ 1. Scientific Philosophy
Cardano is based on a scientific approach and is developed by a team of academics and researchers, making it one of the most rigorously researched and tested blockchain platforms.
¶ 2. Proof of Stake
Cardano uses a proof of stake consensus mechanism, which is more energy-efficient and environmentally friendly than proof of work, used by other blockchains like Bitcoin.
¶ 3. Pluggable Consensus
Cardano is designed to be flexible and allow for different consensus mechanisms to be used, providing the option to switch between them as needed.
¶ 4. Separation of Accounting and Computation
Cardano separates the functions of accounting and computation, making it easier to upgrade and improve the platform without disrupting its core functionality.
¶ 5. Interoperability
Cardano has been designed with interoperability in mind, allowing it to easily integrate with other blockchain platforms and systems.
¶ 6. Smart Contract Platform
Cardano is a smart contract platform, meaning it allows for the creation and execution of self-executing contracts, enabling a wide range of decentralized applications to be built on the platform.
¶ 7. Privacy
Cardano places a strong emphasis on privacy and has implemented advanced privacy features, such as the Plutus programming language, to protect the privacy of its users.
¶ What is an UTxO?
Cardano is an Unspent Transaction Output (UTxO)-based blockchain.
UTxO stands for “Unspent Transaction Output”
Read more here…
or
(e)UTxO here…
¶ What is a wallet?
A cryptocurrency wallet is a piece of software that allows you to interact with the blockchain. Simply spoken, it serves the same purpose as a physical wallet for cash. You store all your digital assets on the blockchain. The wallet is an interface to look at it and move it as needed.
Users may manage their digital currencies/assets with a cryptocurrency wallet, which is a secure way. You store nothing in the wallet itself.
You can restore the same seed phrase in different wallet software to derive the same set of keys and get access to all your digital assets on the blockchain.
You can access the wallet with 2 different keys, the private and the public keys.
You may share the public keys with other people and enable others to see the balance of your wallet or transfer digital assets to your wallet.
Private keys are never to be shared because they enable access to all digital assets in your wallet.
With the private keys, you can transfer assets to other wallets.
A private key is like a password that is required in order to transfer your crypto assets.
“Not your keys, not your coins“
… they have said
Remember:
We regard only a wallet in which you own the private key as a secure place to save your personal crypto assets.
Read more about wallet types here:
Types of wallets (Cardano Docs)
¶ Wallet - settings ... 
¶ Wallet - how to ...
¶ What are xPub-keys?
are a component of the Cardano blockchain standard and are used by many blockchains as well.
An xPub-key is similar to the master view of a wallet. (also read here…)
xPub keys are useful because the Cardano blockchain employs the concept of unspent transaction outputs (UTXOs) in return addresses. This means that every transaction uses the entirety of a wallet’s balance, and any leftover funds are sent to an entirely new, unused wallet address.
An xPub-key allows a full read-only view of all transactions, addresses, and balances in a specific wallet. You may create all the public addresses using the xPub-key (including all the UTXO addresses).
¶ Note:
The private keys needed to perform transactions, however, are not included in an xPub-key.
For instance, tracking a wallet’s complete history can be done with the aid of an xPub-key (e.g. Ledger Nano S, Trezor, Exodus, etc.).
¶ Staking
In ETERNL you can see all the pools that are available. Find a pool you like, check their websites, then delegate to a pool.
Or delegate to multiple pools by adding more accounts, if you have a lot of ADA.
¶
¶ Pre-Production testnet
A pre-production testnet that mimics mainnet parameters. A good playground for newcomers as well as more experienced users when testing Cardano integrations or learning how to operate a stake pool.
¶ Preview testnet
A network for testing release candidates and mainnet releases. Leads mainnet hard forks by at least 4 weeks. If you want to test the latest features, this is the place to do it.
¶ Guild Network
A testnet created and operated by Guild Operators community group with a short epoch for rapid development and testing.
Read more here…