лол, 180 слов за 8 баллов. Как-то не честно, ну да ладно
There are people who claim that there is no better way to verify student's knowledge than to exam him. I totally agree with this statement, I find it a rather good way to check a student. 
To start with, if the exam is in a test form, it take less time for a teacher to make it and for a student to complete it. It is easy to chose between few option and it's much faster than to write down a whole answer. Secondly, it is easy for a teacher to make four or six variants for a class and to observe students at work, than to spend time for each one, having no idea how long may it take. Thirdly, almost all exams have a unified system of exam assessment that makes the assessing unbiassed.
 However, there are people who disagree with this point of view. Most of them say, that it's easy to find answers in internet and cheat. It is slightly possible to cheat or to use a mobile phone when a teacher watches attentively. Some may also mention that some student might be so lucky to be asked exactly about the only theme he has leaned. On that occasion exams are being made various, so that they could exclude that situation.
By the way of conclusion I would say that advantages of exams as a way to check students knowledge outnumber disadvantages, the fact that it the most popular way nowadays just proves it.