Some business need to associate each of the items ordered with a job (or account number).

To do this, you'll use the "Your Cat #" column in the Item.  It's the second column in the Item Area as shown below:

The "Your Cat #" column is an adaptable column and can be used for other purposes.  One primary purpose is for job or account numbers.  You can change the name of of the column by selecting FILE >> BASIC PROGRAM SET-UP & PREFERENCES and clicking on the "User Defined Fields" tab.  In the illustration, below, the name of the column has been changed to "YOUR ACCNT"

To make this process easier, you can activate a pop-up list with your job (or account) codes.  To prepare the content of the pop-up list, select OTHER TASKS >> EDIT/VIEW JOB CODE LIST.

Once you have entered your codes on the pop-up list, you can use it in the Item Area.  To use it, place your cursor on the appropriate row in the Item Area and select STOCK TOOLS >> INSERT JOB/ACCOUNT CODE.  Or you can use CTRL+I or CTRL+Double-click as short-cut keys.  The code that you select, will be pasted in place.

This is explained in much more detail here: Job and Account Codes