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Sheryl Sandberg publishes Lean In

In March, the Facebook (FB) COO released her modern feminist manifesto advising women to fearlessly pursue their professional dreams. The book resonated, selling more than a million copies. Sandberg's message has gained both fans and critics -- and Lean In fueled a larger conversation about "having it all" and the many workplace obstacles keeping women from achieving their professional and personal goals.

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Diana Nyad swims from Cuba to Florida

The professional distance swimmer tried to stroke her way through over 100 miles of shark- and jellyfish-infested water four times between 1978 and 2012, failing each attempt. In September on her fifth attempt, the 64-year-old Nyad finally completed her ambitious swim. Her story and success inspired her fans, whom she told: "You're never too old to chase your dreams."

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Wendy Davis filibusters for 11 hours

The state senator attracted the eyes of the nation as she stood for almost 11 hours filibustering the passage of legislation that would close massive numbers of abortion clinics in Texas. Her stand ended about two hours shy of the bill's midnight deadline, but her fellow Democrats and hordes of protesters in the gallery elongated the delay -- and a vote was held just after 12 a.m., making it moot. The newfound fame inspired Davis to run for a larger office: She's now aiming for the Governor seat.

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Marissa Mayer is ... Marissa Mayer

Though Mayer was appointed Yahoo's (YHOO) CEO in 2012, she can't seem to stay out of the press. Countless publications have profiled her -- and she made three of Fortune's lists this year (MPW, 40 Under 40, and Businessperson of the Year) -- each story sparking a new conversation about the 38-year-old exec. Her multifaceted interests have amassed a trove of diverse fans (and attackers), and all eyes remain on her as she continues to revive Yahoo's troubled brand.

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A record number of women serve in the Senate

The 113th Congress hosted 20 female Senators -- the most in Senate history. The women have been credited with leading bipartisan conversations, helping end the disastrous gridlock that plagued D.C. this fall. Beyond the practiced politicians who've been in office for several terms, some up-and-comers have continuously gained buzz -- keep your eyes on New York's Kirsten Gillibrand and New Hampshire's Kelly Ayotte.

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Amy Poehler and Tina Fey host the Golden Globes

After years of men emceeing the esteemed awards show -- women had only co-hosted, with a fellow by their side -- Fey and Poehler made history by becoming the first female duo to lead the event. Their performance was so well received that the comediennes will be hosting again in 2014 and 2015, silencing those who claim women aren't funny.

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Malala Yousafzai becomes a symbol of peace

The teenage protestor has been standing up to the Taliban since she was 11, advocating for children's education. Last year, she was shot in the head, and it didn't look like she'd survive. She did, wrote a book about the experience, and continues her mission. She was rumored to be nominated for the Nobel Peace Prize this year at 16,which would make her the youngest nominee ever. (Nominations are kept secret for 50 years.) Yousafzai didn't win -- the honor went to the Organisation for the Prohibition of Chemical Weapons (OPCW) -- but her dreams remain big: She hopes to one day become the prime minister of Pakistan.

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Robbie Kaplan and Edith Windsor strike down DOMA

Paul, Weiss partner Kaplan represented 84-year-old Windsor in a case brought to the Supreme Court. In July, Kaplan's work led the justices to strike down a significant portion of the Defense Against Marriage Act, which denied same-sex marriages the same tax, health, and pension benefits as heterosexual marriages, in July. There are still plenty of states without marriage equality and their own mini-DOMAs, but Kaplan and Windsor's success was a huge step toward diminishing such laws.

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Janet Yellen is nominated to be Federal Reserve Chair

In October, President Obama announced his nomination of Yellen to take over Ben Bernanke's role as chief of the Fed. Her appointment will most likely be confirmed before the year's end, making her the first woman to ever sit in this role.

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