Soon Bank of England banknotes will only feature famous men - apart from the Queen - and some people are campaigning to change this.
Elizabeth Fry, a social reformer who worked hard to improve the conditions in prisons during the Industrial Revolution, was on the five pound note.
But Fry is going to be replaced by former prime minister Sir Winston Churchill.
Now campaigners, from a group called the Women's Room, want to find out what goes on in the bank's selection process.
A group of 46 MPs have written to the bank to ask them to reconsider their decision to get rid of Fry, and explain why they chose not to replace her with another woman.
Before a person can be put forward to be featured on a note they have to meet a strict criteria.
They must have made a lasting contribution to society, have a widely recognised name, not be controversial, there must be good artwork on which a design can be based and it can't be a current living person.
On Tuesday the outgoing governor of the Bank of England Sir Mervyn King said author Jane Austen may replace Charles Darwin on the £10 note.
The Queen will stay on the other side of all notes and coins.
We wanted to know who you think should be the next woman to be featured on a banknote, check out some of your answers below.
"I think the Bronte sisters should be on a note because they wrote a lot of very popular books and they are great role models for women."
Ciara, Bristol, England
"I think Rosa Parks should be on a banknote because she changed the world and is a very inspirational woman."
Melissa, London, England
"I think Jane Austen should be on banknotes."
Rebecca, Nottinghamshire, England
"I want Emily Davison to be on my £10 note because she was amazing and changed women's rights."
Emily, Northumberland, England
"Dorothy Hodgkin because she was an amazing chemist."
Holly, Yorkshire, England
"I think Enid Blyton should be on a banknote because she wrote some brilliant stories such as the Famous Five and The Secret Seven."
Zara, Surrey, England
"I think we should have Marie Curie on our banknotes because she is an inspiration to all of us."
"I think Florence Nightingale should be on a banknote because of how she changed the nursing profession."
Anna, County Down, Northern Ireland
"I think it should still be the Queen as she is our leader and everyone knows who she is."
Bethany, Bristol, England
"I think Jessica Ennis should be on a banknote because she is an amazing person and has done Great Britain proud!"
"I think Princess Diana and Winston Churchill should be on but I think there should be suffragettes or women's rights campaigners too."
Anonymous, Herts, England
"I think Beatrix Potter because she is a role model to me."
"I think that Jacqueline Wilson should feature as she has encouraged many people to write and read."
Kylie, Middlesex, England
"I would like the Duchess of Cambridge because she's famous and she's the future Queen."
"Personally, I think Emily Davison should be put on the banknotes, for her fearless battle for women to get the vote and it ended up costing her her life."
Rhys, Stratford-on-Avon, England
"I think Mother Teresa should be put on banknotes because she helped lots of people!"
Ananya, London, England
"I think Princess Diana should because she raised lots of money for charity."
Maya, New Jersey, America
"I think that Princess Diana should be on a banknote because she did so much for our country and she is an inspiration for us all."
Zia, Scunthorpe, England
"I think people such as Ellie Simmonds or Emily Pankhurst should be on there as they are so inspirational. But they should also include inspirational men too."
Astrid, Canterbury, England
"I think Jessica Ennis should be on because she is a really good role model for the rest of the country."
Stella, Cumbria, England
"I think that Margret Thatcher should be on the note, because she was the only woman prime minister of Britain (and she was very influential)."
Sonya, Sheffield, England
"I think either Kate Middleton or the Queen because they are easy to recognise and they are both part of the Royal Family."
Morgan, York, England
"I think a mixture should be going round. Elizabeth Fry should stay but Sir Winston Churchill can be added."
Elizabeth, Kent, England
"I think Boudicca or Florence Nightingale should be on banknotes because they fought for what was right. It's stereotype and silly to think that just men should appear on banknotes."
Evelyn, Tonbridge, England
"The leader of the Suffragettes because she is inspirational."
Isabella, Devon, England
"I personally think that Margaret Thatcher should be on a banknote, due to her decisions England has become a better place to live then then it was before!"
Avi, Birmingham, England
"I think that Florence Nightingale should be because she was a very good woman and was inspirational."
Maisie, Brussels, Belgium
"We think that Grace Darling should be on the £5 note. We have learnt about her brave rescue of the survivors on the SS Forfarshire. Sadly, she died only 4 years after this event. She definitely deserves to be on the note so that more people will be reminded of her bravery."
Cairo Class (Year 1/2), Hollingwood Primary School, Chesterfield, England
"I think that it should be Margaret Thatcher because of how she has shaped the modern Britain and she has recently passed away so the timing would be right."
Theo, Reading, England
"I think Jessie J as she shaved her hair for comic relief and she is a really good role model."
Lu, Suffolk, England
"I think Queen Elizabeth should be the only one on banknotes because it will be easy to know who it is."
Ellie, Southampton, England
"I think Helen Skelton should be on the bank note because of all the amazing stuff she has done."
"I think Kate, the Duchess of Cambridge should as she is very kind and pretty and it would be lovely to have a pretty lady on the bank notes."
Sophie, London, England
"I think they should have everyday heroes, like ambulance workers and midwifes. These women help people everyday and they should get a reward!"
Sarah, London, England
"Jacqueline Wilson because she is an inspirational author and millions of other girls love her bestselling books."
Rosa, Bath, England
"I think that Emily Wilding Davidson should appear on a bank note because she fought for women's rights."
Daniel, Cardiff, Wales