Besides speaking, the other main way we communicate is through writing. If you attend a native English speaking university you will be writing many reports, essays and term papers. You won't get far if you can't get your assignments done. And using the Internet to borrow other people's work will only get you expelled. The TOEFL test Writing section isn't as challenging as writing a term paper, but you definitely have to prove you know how to write a few paragraphs using proper grammar, and how to get your point across clearly and convincingly.
The IBT test Writing section has 2 tasks. 50 minutes is the total time allowed to complete the Writing section. Each of the questions is given a mark of 0-5. Your total score is then scaled to a value out of 30. For a decent score you must get at least 4 out of 5 for both writing tasks.
The only way you'll get scores of 4 or 5 is to practice your writing skills. However, you aren't expected to write a perfect essay for these 2 tasks as the amount of time given just doesn't allow it. Don't think that writing lots will get you a better grade than a shorter essay. If it has many spelling errors, has bad sentence structure, has poor grammar, goes off topic, doesn't express your thoughts clearly or doesn't give examples that support your reasons, you'll still bomb.
What score you get from 0-5 for your writing responses is based on a variety of factors: language use, organization, clarity, and development. Language use means how well you can use grammar and vocabulary. Do you use the same words over and over or have variety? Did you use the right word? How many spelling mistakes did you make? And don't use any slang or swearing. Do you use more than one kind of sentence strucure? Or are your sentences all basic like, "The banana in the basket is green." Development refers to how well you answered the question. Is your essay coherent? It should go from one idea to the next logically. It should be easy to understand, not confuse the grader to death. Your essay should provide reasons – more than one – with details or examples to support the reasons you give. Below is a guideline of what grade to expect for an essay for each of the 2 writing questions.