CipherShed is an Open Source fork of the discontinued TrueCrypt Project. CipherShed is encryption software for keeping your data secure and private.
On-the-fly encryption means that data is automatically encrypted right before it is saved and decrypted right after it is loaded, without any user intervention. No data stored on an encrypted volume can be read (decrypted) without using the correct password/key file(s) or correct encryption keys. The entire file system is encrypted (e.g., file names, folder names, contents of every file, free space, metadata, etc.). Files can be copied to and from a mounted CipherShed volume just like they are copied to/from any normal disk (for example, by simple drag-and-drop operations). Files are automatically being decrypted on the fly (in memory/RAM) while they are being read or copied from an encrypted CipherShed volume.
Similarly, files that are being written or copied to the CipherShed volume are automatically being encrypted on the fly (right before they are written to the disk) in RAM. Note that this does not mean that the whole file that is to be encrypted/decrypted must be stored in RAM before it can be encrypted/decrypted. There are no extra memory (RAM) requirements for CipherShed.
CipherShed is available as an installer which includes a portable option to extract the files only. A restore point is created during the installation as well. Finally, you're offered a link to their beginners tutorial.
It's worth noting that CipherShed is best used by advanced users although there are steps aimed at less experienced users. The user's guide alone is 151 pages to give you an idea of how complicated CipherShed can get.