These are the different classes into which income and outgo are separated. The maximum number of categories you can have in a document is about 32,000 , but practically that number is limited by available memory. In a 512K Mac, you should be able to use about 100-200 categories, if you like.
Each category contains the following information:
Name: Up to 16 characters.
Type: Either a credit or debit. For example, in a checkbook account, deposits are credits and checks are debits.
Auto-Payee: This is an optional feature. An auto-payee is a text string of up to 90 characters. Say in your checkbook account you had a debit category named RENT. Since rent is always payed to the same person, it's a pain to have to type in the same name every time you make a rent entry. An auto-payee let's you specify some text to appear automatically for entries of that category.
Auto-Amount: This is similar to an auto-payee, but it's a dollar amount.
Auto-ON: This is a flag you can switch on and off. When on, it means the category's auto-amount will be entered for you when you select an auto-payee.
Budget-Amt: This is the amount you budget for that category for 1 month. This amount is used in generating Budgets Reports (see below).
Budget-ON: This is a flag which determines if a category appears on Budgets Reports.