Much like other features in Syngency such as divisions and galleries, tasks can have a variety of different types assigned to them.
These are managed alongside other types in Settings > Types. By default, the following task types are available:
You can edit any of these directly by clicking on them, or click the Add Type button in the bottom-right corner of the page to add a new task type.
When you open or add a new task, the Type window will appear as below, allowing you to edit the name of the task type, and the icon which represents it in each task.