For most users, this field indicates base filename (without extension) of the individual entry archive. For example a basename of "my_trip_to_disneyland" might lead to a URL like:

http://www.example.com/2005/06/my_trip_to_disneyland.html

It is based on the entry title and automatically calculated upon entering text into that field. The basename is dirified (spaces replaced by underscores, other punctuation removed) in order to create a valid URL.

If, in creating the entry, the basename field is left unedited, Movable Type will check for basename collisions with other entries. In case of a possible collision, an underscore and incremented number will be appended to the basename (e.g. title1, title2, etc) and the new basename will be displayed after the entry is saved.

If you choose to edit the basename, collision checking is turned off. If the basename you choose collides with another entry, it could cause one to overwrite the other on the published weblog. Also, if you edit the basename of a published entry, it will very likely change the published filename, hence breaking incoming links to the entry. Both of these actions are not recommended unless you know what you are doing.

The entry basename can be displayed using the MTEntryBasename tag. This tag is most useful as part of your Archive Map File Path.

Note: If you have customized your Archive Map File Path to use something other than the basename for your individual entry archives or a different dirification (e.g. using dashes instead of underscores), this change is not reflected in the basename field. This will be addressed in a future version.