All terms
Software that holds your keys and signs transactions. It does not hold your coins.
This word confuses almost everyone at the start. A wallet does not store your crypto. Your coins live on the blockchain. The wallet stores the private key that proves the coins are yours and lets you authorize moving them.
That distinction matters because it explains everything else. Lose the wallet app, no problem, reinstall it and restore from your seed phrase. Lose the seed phrase, and the coins are gone even though they still sit visibly on the chain forever.
Your MetaMask does not contain ETH. It contains a key. The ETH is a number in Ethereum's state that only that key can change.
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