NEW YORK TheStreet-- Leadership positions at some of the largest companies have largely been dominated by men. There are only 21 female CEOs at Fortune 500 companies, with just four of them being tech companies. According to Women 2.0, only 8% of investment professionals at the leading venture capital firms are women. Females also represent only 9% of Silicon Valley Board members. Yet these few women are making major headways in tech. Yahoo!'s ( YHOO) shares have jumped sharply since Marissa Mayer was named CEO. Coming off the back of strong second-quarter earnings, Facebook's ( FB) COO Sheryl Sandberg is inspiring others with her best-selling book, "Lean In." "In the future, there will be no female leaders. There will just be leaders," she writes. Women are increasingly becoming the top earner in their households. Females are now breadwinners in 40% of American family homes. That's four times the ratio we saw in 1960. These are the most powerful women in tech. Here's how they achieved the status they have today.