Few companies that visit the campus duing 6th Semester offer internships where if performed well might earn you a PPO(Pre Placement Offer).
Else, placements start from the beginning of 7th Semester (Mostly August onwards).
Most of the Day 0 companies are IT companies while a few of the core companies visit too during that period.
You will notice more IT companies visiting the campus during the 7th Semester while core ones visiting more during the even Semester i.e., 8th Sem.