There are a few different types of interview settings you may find yourself in, the most common of these are:
Presentations, group activities, written tasks, case studies, portfolios and psychometric tests are some of the sorts of tasks you may be asked to undertake as part of an interview. All of these are designed to do the same thing; employers want to see you showing your strengths, showcasing your areas of skill and what sets you apart from other candidates. Read more about interviews tests and exercises you may come across here.
You may also find this selection of interview tips on Prospects useful.