When you download a from the internet, verifying its file hash is the only way to ensure the file hasn't been corrupted or maliciously altered. Microsoft uses the SHA256 algorithm to uniquely identify official installation files. Why You Must Check the Windows 11 Download Hash
A "hash" is a unique alphanumeric string generated based on the file's content. If even a single byte of the ISO changes—whether due to a bad internet connection or a hacker injecting malware—the hash will no longer match the official version published by Microsoft. Where to Find Official Windows 11 Hashes windows 11 download hash
Finding official hash values can be tricky as Microsoft frequently updates their builds. VERIFY MD5 / SHA256 Hash or Checksum on Windows 11 When you download a from the internet, verifying