The full form of CSAT is the Civil Services Aptitude Test. It was introduced in the year 2011 as a part of the UPSC Civil Services Exam (Preliminary) to test the analytical skills, reasoning ability and aptitude of IAS aspirants.
While the controversy over the introduction of CSAT, officially known as the General Studies PaperII, in UPSC exam still continues, as per the UPSC notification released , the Civil Services Aptitude Test will continue to be a part of the UPSC Prelims.

The syllabus for the Preliminary Exams for Paper-I:
 Current events of national and international importance.
 History of India and Indian National Movement.
 Indian and World Geography - Physical, Social, Economic Geography of India and the World.
 Indian Polity and Governance - Constitution, Political System, Panchayati Raj, Public
 Policy, Rights Issues, etc.
 Economic and Social Development - Sustainable Development, Poverty, Inclusion, Demographics, Social Sector initiatives, etc.
 General issues on Environmental Ecology, Bio-diversity and Climate Change
 General Science The syllabus for the Preliminary Exams for Paper-II:
 Comprehension
 Interpersonal skills including communication skills;
 Logical reasoning and analytical ability
 Decision-making and problemsolving
 General mental ability