It's not a foolproof disguise, but Bill Gates is happy with it.

Sometimes, it really is that simple.

In response to a question during his annual Reddit AMA (ask me anything) session, Microsoft cofounder and richest man in the world Bill Gates says it doesn't take too much for him to blend in with the crowd.

"I sometimes wear a hat," Gates writes. "For example when I did college tours with my son I wanted the focus to be totally on him. A lot less people recognise me when I have a hat on or else they realise I am trying to be incognito."

Gates did not specify what type of headwear he prefers when going undercover, though there are probably a few styles that can be crossed off the list: A classic "porkpie" hat, a la Walter White, seems too dressy for a tech tycoon keeping a low profile, and other styles like a tam-o'-shanter or a fez would also likely be too conspicuous.

READ MORE: Bill Gates is on his way to becoming the world's first trillionaire

​A baseball cap, on the other hand, seems like a good choice.

While there aren't many photos of the pretty straight-laced Gates wearing anything other than business casual, here's a picture of the man in his Seattle Seahawks gear:

And this video, made to thank participants in his 2016 Reddit AMA, shows him wearing a variety of, um, headgear:

Gates isn't the only tech celebrity with a penchant for using hats as a disguise.

When the late Apple founder Steve Jobs met in secret with the publisher of the New York Times at a private Manhattan dinning room in 2010, New York magazine reported that the Apple VIP was spotted sporting "a very funny hat — a big top hat kind of thing."

The hat disguise is not exactly foolproof. But that's OK, writes Gates: "Mostly when people do recognise me they are super nice so I don't feel it is a burden to be noticed most of the time."

And hey, that kind of simple disguise has worked just fine for Clark Kent and Superman for the better part of a century now.

- This story was first published at BusinessInsider.com.au