Encrypting a file or document is the easiest way to prevent other people from accessing its content. Thus, unless we have the password or decryption key it will be practically impossible to see what it contains. In the next post we will see what methods we can use in most operating systems to encrypt a file securely.
Before starting it would also be interesting to clarify that the encrypted files are not 100% indecipherable. A good hacker can (albeit with difficulty) bypass encryption protection. Something that can happen if we keep passwords and cryptographic keys in an unencrypted file or our system is infected by a keylogger. If we have really valuable information, the most recommended solution is to hire an encryption service in the cloud (mainly oriented to companies).