Where can I accept airdrops?

I'm curious, where can I actually accept airdrops of cryptocurrency? I've heard about this concept, but I'm not sure where to look for these free tokens or coins. Are there specific websites, wallets, or social media platforms that typically distribute these airdrops? Is it necessary to hold a certain amount of a particular cryptocurrency to be eligible? And, what precautions should I take to ensure I'm not falling victim to scams when accepting airdrops?