If done correctly, selling cash secured or slightly levered puts is one of the most lucrative and simplest of options trading strategies.
A thread on Cash Secured Put selling.
ATM puts make up their premium from in part the equity premium and partly the volatility premium.
The equity premium is simply the premium you get paid for holding the stock for long periods of time.
Puts marry these together.
It is best run on options of a diversified stock index where there is a good likelihood of the option implied volatility being higher than realized volatility.
I said, well diversified stock index where the implied vol stays above realized vol.