The worldwide event aims to raise awareness about the need to protect the environment
Millions of people across the globe are gathering to mark Earth Day and celebrate the environmental movement.
Earth Day is a global event which aims to highlight the importance of protecting the environment.
The first Earth Day saw 20 million people across the US take to the streets.
"Celebrating Earth Day is often the first environmental action for a lot of people," says Earthday.org president, Kathleen Rogers.
What is happening for Earth Day 2024?The 2024 theme, "Planet vs. Plastics", aims to raise awareness of the harms of plastic pollution for human and planetary health.
More than 50 countries, including the UK, have called for an end to plastic pollution by 2040.But the organisers of Earth Day want to go further, and are calling for a 60% reduction in the production of all plastics by 2040.
Within a few years of the first Earth Day in 1970, the US Environmental Protection Agency had been set up, and several environmental laws - such as the Clean Air Act - had been established or significantly strengthened.
"With a host of issues driving our environmental challenges down society's priority list, events like Earth Day remind us of the long-term cost of short-termism," says Yvo de Boer, former UN climate chief.
In 2016, Earth Day was symbolically chosen for the official signing of the landmark Paris climate accord, which had been agreed in late 2015.It was the first time that countries of the world had collectively agreed targets to try to limit global warming.
"We all know greenwashing is happening and it is infuriating," Earth Day organiser Ms Rogers told BBC News."It's not an issue we've caused, but we know Earth Day is used cynically by some businesses to [mis]use the ethos of sustainability for their own gain."