This year’s International Women’s Day, and their theme #BalanceforBetter, really struck a chord with me. Despite women holding 57 percent of all professional positions in the U.S., they account for just 25 percent of professional computing workers. So what gives?

This glaring imbalance inspired me to honor eleven of the most inspirational women in tech who have ever lived, past and present. In their own ways, each of the women on my list has made their mark on technology and blazed a trail for others to follow, often by going against societal norms. By setting examples that women from all backgrounds can follow, these eleven inspirational women in tech, both historically and currently, deserve special recognition.

1. & 2. Sara Chipps and Vanessa Hurst

Sarah Chipps and Vanessa Hurst are the co-founders of Girl Develop It, a phenomenally successful nonprofit organization that helps women learn about software and web development. From one class in 2010, Girl Develop It has expanded to more than 60 cities spread across 30 states. By empowering women of all backgrounds and skillsets to learn how to code, Chipps and Hurst are helping to create greater career opportunities for thousands of women. I’m confident that the trends and technologies that power tomorrow’s world could well be designed and coded by a Girl Develop It alumni!

3. Reshma Saujani

In 2010, Reshma Saujani smashed through another layer of the glass ceiling by becoming the first Indian American woman to run for U.S. Congress. Her experiences during the election race convinced her that the gender gap in high school computing classes was a problem in search of a solution. She subsequently founded Girls Who Code as a way of closing the gender gap in tech. To date, Girls Who Code has helped over 90,000 girls across the U.S. improve their coding skills. According to their website, Girls Who Code alumni are 15 times more likely to major in Computing Studies than their peers, underscoring the incredibly powerful role that Reshma occupies in today’s tech landscape.

4. Kimberly Bryant

With over 20 years’ experience in the pharmaceutical and biotech industries and at various Fortune 100 companies, Kimberly Bryant is one of the most inspirational women in tech right now. As the founder of Black Girls CODE, Bryant is helping young women bridge the digital divide and encouraging girls and minority young women to hone their coding skills. Black Girls CODE has trained over 2,000 women, helping to carve out an entirely new generation of coders, and Bryant’s position as an inspirational tech trailblazer is undisputed.

5. Megan Smith

As the first female CTO in U.S. history, Megan Smith helped guide the Obama administration’s IT policies and initiatives towards greatness by harnessing the power of data innovation. After leaving the White House, Smith launched the Tech Jobs Tour which hosts a series of networking, mentoring and jobs-fair events across the country. Smith’s role in helping females and other minority groups into tech has helped solidify her position as one of the most inspirational women in tech of all time.

6.& 7. Dorothy Vaughan and Katherine Johnson

When NASA needed raw computing power to enter space in the 1960s, Dorothy Vaughan and Katherine Johnson were among the many women who they turned to for help. Vaughan and Johnson were African American mathematicians who acted as ‘human computers’ and calculated the orbital trajectories of the first space flights.

Among many other accomplishments, Johnson calculated the Apollo 11 trajectories and those used by the Space Shuttle missions. After being awarded the Presidential Medal of Freedom in 2015, NASA dedicated a building at its Langley Research Center in Johnson’s honor.

Meanwhile, Vaughan was the first black NACA supervisor in 1949 and, following desegregation, became an expert FORTRAN programmer, contributing to the Scout rocket program later in her career.

8. Ruth Amonette

After joining IBM in 1939, Ruth Amonette rose to become the company’s first female vice president in 1943, at the age of just 27. The trials and tribulations of her inexorable rise were chronicled in her autobiography, Among Equals. Amonette is renowned both as a businesswoman and as an educator and is widely regarded as one of the most inspirational women in tech to have ever lived.

9. Grace Hopper

Grace Hopper aka the ‘Queen of Code’, virtually invented coding during the 1940s. After joining the U.S. Navy in 1943, Hopper helped produce the Harvard Mark I computer and was one of the first programmers, during which time she coined the term ‘bug’. Convinced that an English-based programming language was possible, Hopper developed a program compiler (later known as a program linker) that could convert English terms into machine code understood by computers.

Hopper amassed 40 honorary degrees from universities across the world during her life and a Yale University’s Hopper college was renamed in her honor. She was posthumously awarded the Presidential Medal of Freedom by President Barack Obama in 2016, some 32 years after her death.

10. Ada Lovelace

Ada Lovelace is widely considered to be the world’s first computer programmer. In the mid-1800s, English computer pioneer and mathematician Charles Babbage asked Lovelace to translate an article about his proposed mechanical computer, the analytical engine. Lovelace not only translated the article, but she also expanded it by theorizing a way of getting the machine to repeat a set of instructions, something that would later become known as ‘looping’. Her work was published by an English science journal in 1843 but her contributions weren’t widely recognized until the 1950s. In the 1980s, the computer language ‘Ada’ was named after Lovelace by the U.S. Department of Defense.

11. Margaret H. Hamilton

Renowned computer science pioneer and mathematician Margaret H. Hamilton rounds off my list of the top eleven influential women in tech. Widely considered to be the founder of software engineering, Hamilton coined the term ‘software engineering’ while heading up the Software Engineering Division of the MIT Instrumentation Laboratory.

Many male software engineers are surprised to discover that the founder of their discipline was, in fact, a woman. But even more surprising is how hard Hamilton had to fight to gain software engineering the same respect as other disciplines. In a recent interview, Hamilton revealed that her ideas were considered ‘radical’ while she was working to develop the guidance and navigation system for the Apollo spacecraft. “When I first started using this phrase, it was considered to be quite amusing,” she said.

Currently serving as CEO of Hamilton Technologies, Inc, Hamilton received a Presidential Medal of Freedom in 2016, cementing her position as one of the most influential women in tech of all time.

The eleven women on my list have worked tirelessly to challenge bias and chip away at the glass ceiling of gender discrimination. Their inspirational and inspiring accomplishments have helped encourage more women to move into technology than at any point in history. Thanks to them, more women than ever are moving into tech and helping to solve some of the world’s toughest problems.

What did you think of my list? Who did I miss? Let me know by leaving a comment below!