On Friday, people from nations all over the globe took part in the Global Climate Strike, which was inspired by the teenage activist Greta Thunberg who started the movement in 2018.
Back in August of last year, the Swedish teenager was photographed outside parliament in Sweden on a Friday, during school hours, where she was holding a sign that read 'school strike for climate.'
Many could have easily dismissed her as just another young activist trying to make a point about the dangers that the planet is facing but something happened and her message began to resonate with people everywhere.
Millions of people are said to have taken part in Friday's Global Climate Strike, with people of all ages marching in cities ranging New York to Mumbai and nations like Pakistan, Uganda and Tuvalu, a Pacific island, home to just over 11,000 people.
I would never have predicted or believed that this was going to happen someday. And so fast, only in 15 months.
I can't wait to see the official numbers come in. It will be magnificent.
Thunberg might not have anticipated her activism sparking such a huge movement but there is no denying the positive influence that she has already had on the planet.
In a now-viral tweet, Twitter user James Shield shared an image of Thunberg, on her own with her sign in 2018 and the thousands of people who took to the streets of New York on Friday in support of her message.
These two completely contrasting images, which carry the exact same message has now been shared more than 13,000 times on Twitter and people are full of praise for Thunberg and for what she has started.
This week has been agonizing for a lot of people. But I know hope because of this. https://t.co/QcNwM75Avx