A session file is the document that Pro Tools creates when you choose File > New Session and configure a new session. Pro Tools can open only one session file at a time. The session file is named with a .ptx (Pro Tools file) extension. Session files contain maps of all elements associated with a project, including audio files, MIDI data, and all your edit and mix information. It is important to realize that a Pro Tools session file does not contain any media files (audio or video). Instead, it references audio, video, MIDI, and other files. You can make changes to a session and save those changes in a new session file. This lets you create multiple versions of a session or back up your editing and mixing work.
