Will changing a file's name affect the file's MD5 or SHA1 hash value?

Changing a file's name does not affect the file's MD5 or SHA1 hash value because these hash functions calculate the hash based solely on the file's content, not its metadata, including its name. The hash algorithms process the binary data within the file itself, producing a unique fingerprint based on that data.

For instance, regardless of whether a file is named "document.txt" or "report.txt", the underlying byte sequence—the actual content of the file—remains unchanged, leading to the same hash value. Hash functions are designed to provide a fixed-size output against the input data, so unless the content of the file is altered, the hash remains identical despite any change in the file's name.

This understanding is crucial in digital forensics, where maintaining data integrity is vital, and hash values are often used to verify that files remain unaltered throughout the investigative process.