You can annotate users to store information about them such as, for example, gender.
Click Tools-->Show avatars to bring up the avatars panel. This panel may look like a list, but is actually a table with only one column by default. This means you can add additional columns to it.
Right click (Ctrl+click on the Mac) on the table to bring up a popup menu. You can add columns, rename them or remove them. The first column can be neither renamed nor removed.
You can edit any of the columns except the first one. Just click in the cell you want to edit and type. Press enter to finish editing. Any data you enter in this table is saved to the database when you press enter or any other key so you don't have to hit save or anything and you will not lose any data unless there is a catastrophic crash, i.e. something which VWTk cannot detect, like turning your computer's power off!
Annotations you make to the data are reflected in the visualization immediately. Hover over any symbol to see the annotations for that user.
