Facebook COO Sheryl Sandberg is undeniably one of the most powerful women in business. The Harvard-educated billionaire has been instrumental in turning Facebook into a real (i.e., profitable) business. And thanks to her popular manifesto on women and work, she's coined a term--"lean in"--that's inspiring women of all generations to become leaders in their jobs. Sandberg knows a thing or two about building a big business, but what about the everyday challenges hard-working women experience in the workplace? She has quite a bit of sage wisdom about those, too.

Here are five of her key insights on succeeding at work.

1. On institutionalized sexism:

"If you ask men why they did a good job, they'll say, 'I'm awesome. Obviously. Why are you even asking?' If you ask women why they did a good job, what they'll say is someone helped them, they got lucky, they worked really hard." --TED Talk, "Why We Have Too Few Women Leaders," December 2010 

2. On breaking the status quo:

"I'm a pragmatist. I think, as a woman, you have to be more careful. You have to be more communal, you have to say yes to more things than men, you have to worry about things that men don't have to worry about. But once we get enough women into leadership, we can break stereotypes down. If you lead, you get to decide." --Stanford lecture, April 2013

3. On finding the right fit at work:

"At Facebook, we try to be a strengths-based organization, which means we try to make jobs fit around people rather than make people fit around jobs. We focus on what people's natural strengths are and spend our management time trying to find ways for them to use those strengths every day." --New York Times interview, March 2013

4. On calling careers a "jungle gym, not a ladder":

"There's only one way to get to the top of a ladder, but there are many ways to get to the top of a jungle gym. The jungle gym model benefits everyone, but especially women who might be starting careers, switching careers, getting blocked by external barriers, or reentering the work force after taking time off. The ability to forge a unique path with occasional dips, detours, and even dead ends presents a better chance for fulfillment. Plus, a jungle gym provides great views for many people, not just those at the top. On a ladder, most climbers are stuck staring at the butt of the person above." --Sheryl Sandberg, Lean In: Women, Work, and the Will to Lead

5. On how to push yourself to be more brave:

"What would you do if you weren't afraid?" --Sheryl Sandberg, Lean In: Women, Work, and the Will to Lead