Apple’s co-founder said the key to being happy is laughter, not money

His net worth is $100 million (€88m), yet Steve Wozniak believes happiness has nothing to do with dollar signs.

The engineer, who founded Apple along with Steve Jobs and Ronald Wayne, believes that the formula for being content with your life is "smiles minus frowns."

Speaking to CNBC this week, said that smiling "was my original formula when I was about 20 years old.

"Create jokes, create humour everywhere you go. That keeps you happy."

He also noted that when facing challenges in your life, you need to be resilient, and you can't hang onto things that go wrong.

"Don't be bothered when things don't go your way. Just think out how to be constructive… don't waste your time blaming people and being upset, because those feelings will destroy your psychology."

So, in other words, if you feel your life has taken a U-turn, or you're not in the place where you thought you'd be, stay strong, and you know… keep on smiling.