Key takeaways: Private keys and addresses
EIP-55 adds a checksum to Ethereum addresses using a mix of uppercase and lowercase letters. If a few characters in an address are mistyped, most checksum-enabled wallets can detect it.
Bitcoin and Ethereum private keys are essentially both large 256-bit random numbers, and both use the secp256k1 elliptic curve.
After pasting an address, double-check a few characters at the beginning, end, and middle—don't just check the first and last characters.
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