The format of the TOEFL test has been changed three times. The first was the PBT (paper-based TOEFL test). It tests listening, reading and grammar skills with a perfect score being 677 (Paper Based). Some centers where computers are not available still offer this format. The second format is the CBT (computer-based TOEFL test). People are each provided with a computer to take the test. A writing section was added as well as the three sections. The level of listening and grammar skills are automatically changed depending on a person’s English level. The third change is the iBT (Internet-based test) that is being brought in around the world which measures listening, speaking, reading and writing.