Hi Bulbul,

Freshers and less experienced candidates (less than 2 years)are required to qualify the written test as part of their interview process. The test is basically divided into two sections, with 75% questions related to pure English grammar and the remaining 25% related to tools and computer basics.
Generally, the candidate is selected by his/her performance in language test rather than tools.
Experienced candidates are exempted from written test, while the panel may ask typical questions related to their past project experience.

Hi

Though it is true what srip has suggested, it is not always true. Many comapnies prefer having technical writing tests even for hiring experienced tech writers - to know their technical writing skills.

For example, they may give you some draft of an instruction-set and candidate need to re-structure it and write in a formal User Manual kind of document (they set up a PC for that).

Besides, I have seen that many companies ask a QA based Essay test where many of their interview questions are automatically answered. This helps companies to know the candidate well in advance for the interview.

Regards
Vinish