Category defines a class of spending or income. AceMoney has a built-in list of the most common categories for personal finance management. It is very important to assign a category for every transaction if you want to keep an eye on your money flow.
This page allows to add, delete and change existing categories.
Also, if a size of a file is important, you might want to get rid of all unused categories by pressing a corresponding button. In general it's not a very good idea, but you can do it if you want.
The other important property of category is budget limit. Once you've decided what is the most convenient budget period for you, you can set up the limits for that period in Category properties dialog. Again, the limits depend on budget period, so think about a period of time before you start entering them.
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