See Where Your Money Goes: How to Categorize and Update Your Transactions in Quicken
When you download your transactions into Quicken, Quicken automatically tries to categorize your transactions based on where the transactions originate, so you can have an accurate idea of where your money goes and how you are spending it. For instance, if you make a purchase at a grocery store, Quicken categorizes the transaction under Food & Dining:Groceries.
If Quicken is unable to categorize the transaction, Quicken will alert you. Simply click on the alert (seen below) so you can choose the correct category for that transaction.
Quicken has its own built-in categories, although you have the abilities to add or remove categories to align with your personal needs.
Each time you update your accounts in Quicken, you will want to go through your transactions to ensure they are properly categorized. To update your accounts, click on the circular arrow next to Accounts on the top left side of Quicken. This is called the One Step Update.
Before you update your accounts through the One Step Update, you can select which accounts you would like to update. Remember to enter your passwords in for the proper accounts to the right. Once you are satisfied with your account selection, click on Update Now at the bottom. When finished, you can go into the account registers you have updated the accounts for and review any new transactions.
If you would like to have Quicken automatically update your accounts when Quicken starts, click on Edit on the top menu bar and select Preferences. Check the box next to Download Transactions when Quicken Starts.