Mayer was employee number 20 at Google. During her 13 years at the company, she held key roles in Google Search, Google Images, Google Books, Google Product Search, Google Toolbar, iGoogle, Google News and Gmail, according to Wikipedia.

She is widely respected in Silicon Valley and, it seems, on Twitter:

Fifteen years ago Yahoo was cutting-edge company.  It, along with  Netscape, Ebay, and America Online, was a darling of stock-market speculators. Today, Yahoo continues to rack up tons of page views, but is clearly overshadowed by Apple, Amazon.com, and Google, as well as newer social media companies such as Facebook, Twitter, and LinkedIn. Facebook, in particular, seems to be a major threat given its ability to target display ads with surgical precision — something Yahoo cannot yet do.

Mayer — the fifth Yahoo CEO in five years — clearly has her work cut out for her:

Some might think it would be difficult to be both a good mom and a good CEO, given the intense demands of both jobs (especially if the mom doesn’t hire a nanny). Twitter users, however, think those concerns are antiquated:

On that note, this Twitter user makes a good point:

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