First of all, IELTS is made up of four subsections based on the four language skills: listening, reading, writing, and speaking. Interestingly, the productive skills, speaking, and writing, are scored very differently from the receptive skills, reading and listening. In addition, the qualifications needed to mark the different papers vary significantly.  Different countries and institutions ask for different IELTS scores. Therefore, students need to check with the relevant authority to find out the scores they need.