Sunday is International Women's Day, a day in which people around the world celebrate the successes of women and recognize their struggles. Many might first find out about the day by seeing Google's Doodle that marks the occasion. Here are some more details.

International Women's Day started in 1908 as a socialist holiday. It was designed to applaud the demands women had for economical and political equality and to denounce oppression of women, according to Heavy.

The first official International Women's Day was held in 1914, and it was held on a Sunday because that's when most women would have time off work.

Finally in 1977, the United Nations recognized International Women's Day as a holiday. Beginning in 1996, each International Women's Day has had a theme. This year's theme is "Empowering Women, Empowering Humanity: Picture it!"

Today, many women are celebrating successes, and one in four women are doing well enough to be considered thriving. However, 2 billion women described their condition as "struggling" or "suffering," according to a Gallup survey, US News reports.

The U.S. ranks just seventh in the world for women who say they are thriving in life. Iceland, Sweden and Denmark are the top three countries where women describe their lives as thriving. The women suffering the most are in Bulgaria, Afghanistan and Armenia.

Women still lag behind men in yearly wages. According to U.S. census data, in 2013, women had a median income of $38,097 per year while men made $48,099 per year.

Women are, however, getting more educated in recent years. According to a White House report, women ages 25-34 are earning more bachelor's and graduate degrees than men.

More women are being given more access to benefits like maternity leave. Certain states are offering paid leave for child birth and to care for their family.

Women continue to make strides in overcoming inequalities. President Barack Obama wants to enact the Paycheck Fairness Act to allow employees more legal rights to pursue wage discrimination against their employers. This could be a key step in getting women equal pay.

Google celebrated International Women's Day Sunday by updating their Doodle image depicting various women in different workplaces and activities. Unfortunately, it's not one of the fun interactive Doodles, but be sure to check out Google's front page and click on it for more on this important day.

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