Tag and Category Management
The key difference between categories and tags is that each post can only have one category, but can have different tags for it. It is useful to consider categories as a method of organising your blog. If you are creating a food blog, you would have categories such as [Breakfast], [Brunch], [Dinner] and so on. Tags might then be features that each meal has, so for example [Japanese Cuisine] or [Orchard Road].
Categories: Every post must have a category, and they are hierarchal. That means that a category can be a sub-category must have a category, and they are hierarchal. That means that a category can be a sub-category to another category, so for example perhaps in the [Breakfast] category you can include the [Cheap Breakfast] and [Luxurious Breakfast] sub categories, and each post will belong to one of these categories. It is important to think about the main distinction between your posts, and then use categories to partition them.
Tags: A post can have multiple, or no tags. They are optional, but similar to categories allow you another method to sort and organise your posts. It is useful to think of other ways of dividing up your post content, and using tags to identify common features like say [Japanese Cuisine] for all posts whether they are lunch or dinner, or perhaps a location tag to allow people to search by location.
Tags and Categories are useful for Users because it provides a good way to find content that they are interested in, and allowing the grouping of posts with common features helps users navigate your ePortfolio better.