Thank You Loveboard. Your reply gets me somewhat idea about bounty & airdrop. I think I will get clear idea when I will participate in any such program. Anyway Thanks for your help.
Bounty programs are varied and all have different duties. For example, twitter bounty programs usually involve you tweeting, following, and retweeting, and then you get stakes (convert into the alt) at the end of the bounty period.
There are also signature bounty programs (just like u see I have a signature that's advertising an ICO). There you just post weekly a minimum amount of posts, then you're awarded stakes.
Airdrops are a different animal. You can do whatever you want to get an airdrop, there are usually very minimal requirements, like joining a telegram channel or simply posting your eth address or simply just holding a coin (in the case of forks) and you automatically get the new alt.