Overview (Introduction begins here!!)
The Preliminary Examination conducted by Union Public Service Commission for Civil Services Examination is commonly known as CSAT or Civil Services Aptitude Test. UPSC now judges to choose Civil Servants on the knowledge of aptitude reasoning and analytical brain. The UPSC has made the CSAT as compulsory exam of only qualifying nature and one has to get 33% marks in it.
The further details of this examination is given on the following page: https://www.brainbuxa.com/exams/indian-administrative-services-examination-ias-2016