Cryptocurrency.
First things first you cannot physically hold crypto, it lives on a decentralized network digitally. That decentralized network keeps track of transactions on a digital ledger called the blockchain. It’s called crypto because it’s secured by cryptography, making it impossible to counterfeit.
Blockchain.
Basically, a public digital ledger that’s shared amongst a vast network of computers. Transactions on the network are recorded and confirmed by these computers and the block is added to the chain.
Bitcoin.
In 2008 a paper published by Satoshi Nakamoto titled “Bitcoin: A Peer-to-Peer Electronic Cash System“ spawned a real-world application for blockchain technology using Bitcoin as its token. Satoshi coded a finite limit to the Bitcoin supply, 21 million BTC will ever exist.
Altcoins.
Any other cryptocurrency that is not Bitcoin. Popular alts are Ethereum, Cardano, and Polkadot. They share similar characteristics, but some more than others offer special utilities, like smart contracts or low transaction fees.
Wallets.
Hold your private keys. Since your crypto lives on the blockchain your private keys give you access to your crypto. If you lose your keys, you lose your crypto.