absence is a calendar tool for keeping track of people (but could be adapted for any other object) on a daily basis. It is meant to replace that ubiquitous whiteboard in the office of the boss. You know the one, where someone has used a permanent magic marker to mark a matrix, and vacations/training/etc. are marked with non-permanent markers as blocks. absence is a CGI system, and has a resolution of one day. It is not intended to be used for keeping appointments or any other activity that requires a finer resolution. It generates an image for each month to be displayed using the GD library, and it can be configured to produce PNG or GIF (or even JPEG).