Hi Ravi,

AAT stands for Architectural Aptitude Test. After a candidate clears JEE-Advanced, he/she could either choose to pursue a course in either Engineering or Architecture. If he/she decides to go with Engineering (B.E. or B.Tech.) or Architecture (B.Arch.) courses in any college except IIT Roorke and IIT Kharagpur, he/she can apply with the JEE_Advanced score. However, for admission to the B.Arch. course at IIT Roorke or IIT Kharagpur, one has to clear the AAT exam.