How to find hash value of a file?

It’s quite simple, really. Your operating system likely has built-in command-line tools. On Windows, have a look at the 'certutil' command. For macOS or Linux, 'shasum' is your friend. You just point it at the file and specify an algorithm, such as SHA-256. It then generates a unique signature. This is brilliant for verifying a download's integrity against the source. You can also find plenty of third-party programmes with graphical interfaces if you prefer.