A previous feature is broken or having issues.

Related to the core functionality or main logic of the project.

Describing how something works, either in reademe's, code comments, or externally to the project.

Very important, or possibly part of the next release.

Actively being worked on.

Low importance, at the current time.

Pertaining to how the end user interacts with the project (for non-WebBrowser projects).

Pertaining to Unit Testing or Testing in general.