Autosave. It is really important to save your work on a regular basis and it is really important to back up your files. Autosave allows you to automatically save your work or to automatically backup your work. I choose the option to automatically back up my work and to keep the last five copies. This is saved me a lot of trouble from time to time when Vectorworks crashes or when I have a problem with a corrupted file.
You can use the Vectorworks autosave to automatically save your file, or you can use it to create a backup. The backup option is my favorite, because it gives you several versions of the same file. You can set the time interval, and you can set the number of backups you keep. This option has saved me several times.