Published in 2001, SHA256, short for Secure Hash Algorithim, is one of the six variants of the SHA-2 algorithims that outputs a 32-byt / 64-hex hash. OP_SHA256 is rarely used by itself, however, it is frequently used through the more common OP_HASH160 & OP_HASH256 operations (included in scripts such as P2PKH & P2SH).
OP_Code Walkthrough
Hashes the top element with the SHA256 algorithim
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Hash with sha256 hashing algorithim
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