TOPIK is basically an SAT type test over your fluency of the Korean language. If you are passionate about this language, wanting to build your resume, or wanting to work one day in Korea or at a Korean company, taking the TOPIK is very helpful.
TOPIK has 6 levels. Level 1 being basic to Level 6 "practically" fluent. Below is how the levels are seen in fluency:
Level 1-2 = Basic
Level 3-4 = Intermediate
Level 5-6 = Advanced
The 6 levels are separated into two difference tests. Level 1-2 is covered in the TOPIK I test while the remaining levels 3-6 are covered in the TOPIK II test. For TOPIK I, the test will cover only reading & listening. TOPIK II covers reading, writing & listening.
The book series TOPIK Master (SEE ABOVE) , is a great series to begin studying for this test. Recently TOPIK updated its tests, so the books might not cover the test exactly as it once did, but the series will still help in learning Korean efficiently. This books comes in the three levels of the test (basic, intermediate, and advanced). It is also offered in Chinese and Japanese!
The only downfall to these book is if you do not know all vocabulary/grammar points, it may be a bit difficult. If you are still in the process of learning, this book can sometime cause a challenge because it doesn't always explain what some questions are saying, or what grammar points are being used.To fix this problem, Korean Grammar in Use (SEE ABOVE) is a great book series to use hand in hand with the TOPIK masters. This book is a series of 3, Basic and Intermediate, and advanced. The beginner book covers ALL grammar used in TOPIK levels 1-2, while the Intermediate book covers ALL grammar in TOPIK levels 3-4 and so forth.
What is great about these books is unlike most language books, they focus only on grammar points. They don't throw listening, grammar, reading and vocab lists at you all at once. They separate the grammar points into groups according to what they are used for. They offer great descriptions on how the grammar point is used and what grammar it is similar to in English. It gives you short conversation using the grammar and then offers you some practice problems to use them. I really really like these books, because it lets you focus on one part of a language the most. It is really help to use to learn and to pair up with the Topik Master books when you are unsure about what a sentence or question is asking you.
As for vocabulary, there are several books here and there that just list vocabulary. However, the website www.topikguide.com , has a lot of helpful information about the TOPIK tests and also documents that can help while studying. They have lists of vocabulary that have shown up on past tests with their english correspondent. It is very easy to print out and carry around.
I hope this post helps you if you are planning to take this test. If there is anything I might not have covered above, please feel free to leave a comment and I will be more than happy to give you an answer