Short codes are just an easy way to refer to contacts or tasks in the log bar drop-down. Think of it just like a Twitter Username. You can set a short code to anything you’d like - just make it memorable.
To access the list of contacts in the log bar press the @ key (SHIFT + 2), or for tasks press the # key (SHIFT + 3).
To change a contact’s short code, click the Contacts tab, search for the contact you’d like to change, and click “edit”.
To change a task’s short code, click the Tasks tab, search for the task you’d like to change, and click “edit”.