The IELTS Writing modules test your ability to produce two quite different pieces of writing in a fairly short period of time. Before applying to sit the test, you need to decide whether to take the Academic or the General Training module.
In IELTS, there are four papers: Listening, Reading, Writing and Speaking. There are two different IELTS modules: Academic and General Training. The Speaking and Listening tests are the same in both modules, but the Reading and Writing tests are different.