I see advantage of using container in it that offer work with more files rather than with one but is there some advantage in encryption technique?I would like to know if it encrypt each single file in a container (or an archive) or is there some another technique used to encrypt it?I want create my own file container as a school project and add some features like encryption etc. therefore i would like to gain more complex overview firstly.
Both ways are possible: encrypting the whole archive or encrypting each file in the archive. Encrypting each file separately is more flexible because this way each file could be encrypted with a different key if needed and each file could be extracted separately, i.e. no need to decrypt the whole archive to get a single file. It comes with a bit more overhead though.
From the security perspective both ways can provide sufficient protection of the content if properly implemented.