Sometimes you may need to add a bunch of categories where only the title is uniuqe, all other fields can be the same. To do this, add a category with the name title1[,]title2[,]title3[,]title4 ... this will cause four new categories to be added named title1, title2, title3 and title4. You can add as many at once as you need, just separate each name with [,]. Note that all the new categories will become children of whichever category you selected as the parent, and they'll share all other info as well, so if you need unique descriptions for each this may not be useful to you (though you could edit the descriptions back in later, leaving it blank initially).

For more complex bulk addition of categories and subcategories, go to Admin Panel -> Categories -> Add Categories and use the bulk add options there. You can add them to a specific parent or add a set of subcategories to all categories at a specified level. You can also import a CSV or other flatfile database of categories.