Definition
What is Private key?
A private key is the secret number that controls an address; whoever holds it can sign transactions and move its funds, so it must never appear in source code or a browser tab.
Deploying from an IDE should always go through a wallet extension that keeps the key isolated, rather than pasting the key into a text box.
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Definition by Adwait Keshari, founder of Monsmith.
See it in practice
Open Monsmith, paste a contract, and watch the audit and profiler explain it.
Open the studio