This week, 37-year-old Marissa Mayer became CEO of Yahoo, an internet provider with many problems, although an audience isn't one of them -- the company claims more than half a billion people currently access its products a month, and Mayer told the New York Times she considers it "one of the best brands on the internet."

Mayer also announced Tuesday that she is pregnant. She and husband Zack Bogue are expecting a baby boy in October.

A Silicon Valley veteran, Mayer became Google's 20th employee in 1999, after completing a Masters in Computer Science at Stanford University. She leaves Google after 13 years, having heading up its search team and, for the last two years, leading location and maps services. This year, she also joined the board of retail giant Wal-Mart.

Now, one of the most powerful women in the tech industry, Mayer regularly shares her philosophies on life and work. Here, we've gathered together some of the lessons that have helped Mayer on her way to the top.

11 fun facts about Mayer

Push through your uncertainty

"I always did something I was a little not ready to do. I think that's how you grow. When there's that moment of 'Wow, I'm not really sure I can do this,' and you push through those moments, that's when you have a breakthrough. Sometimes that's a sign that something really good is about to happen. You're about to grow and learn a lot about yourself," she told CNN in April

Protect what's really important to you

"I have a theory that burnout is about resentment. And you beat it by knowing what it is you're giving up that makes you resentful. I tell people: Find your rhythm. Your rhythm is what matters to you so much that when you miss it you're resentful of your work...So find your rhythm, understand what makes you resentful, and protect it. You can't have everything you want, but you can have the things that really matter to you. And thinking that way empowers you to work really hard for a really long period of time," said Mayer in Bloomberg Businessweek earlier this year.

Work with smart people

"It's really wonderful to work in an environment with a lot of smart people. One, I think because it challenges you to think and work on a different level," she said during a talk at Stanford University's Entrepreneurial Thought Leader Speaker Series in 2006.

Keep some outside perspective

"I've always loved baking. I think it's because I'm very scientific. The best cooks are chemists... I'm a businesswoman first and foremost (but ) my hobbies actually make me better at work. They help me come up with new and innovative ways of looking at things," Mayer said in an interview with San Francisco magazine in February 2008.

Work with a target customer in mind

"I always put the user first when I get ideas pitched to me. I like to think of my mom and wonder if she would be able to get an idea right off the bat," she told careers website WetFeet.com in 2008.

Set constraints to boost your creativity

"People think of creativity as this sort of unbridled thing, but engineers thrive on constraints. They love to think their way out of that little box: 'We know you said it was impossible, but we're going to do this, this, and that to get us there," Mayer said in an interview with Fast Company in February 2008.