Categories let you organize your Outlook items into specific groups, making it easier to find what you’re looking for with just a glance. You can choose from the default categories, or you can create your own.
Categories work across all areas of Outlook. This means that you can give emails, meetings, contacts, and tasks the same category designation to keep track of different responsibilities.
Expand the Tags group, if necessary.
Click the Categorize button.
A list of categories appears. Outlook includes some color-coded categories by default, but you can create your own.
Select a category.
The category is assigned to the selected item.
You can assign multiple categories to an item.
You can also right-click the item, select Categorize and then select a category.
The default color categories are simply named after the color they use. If you find yourself using them frequently, you can change the name to something more meaningful.
Expand the Tags group, if necessary.
Click the Categorize button.
Select All Categories.
The Color Categories dialog box appears, listing all the categories that have been set up.
Select a category.
Click Rename.
Enter a new name.
Click OK.
The category is updated with a new name.
You can also change a category’s color by selecting it, clicking the Color list arrow, and selecting a new color.