No matter how hard you work but during appraisal you will be eligible only for 3%-5% hike.
It gives only a brand name to your resume. You will get good offers form other organisation based on brand name TCS.
Even if you work very hard you will be unnoticed no appreciation here.
As a trainee you will be compared with experienced people. when you become experienced you will be compared with trainees as management will always say your work can be even done by a trainee or when you are a trainee, try to work like experienced people will be remarks by manger during appraisal.
HR is for name sake they are not helpful at all.
Nothing much to learn here.