Earth Day is a globally recognized event celebrated annually to demonstrate support for environmental protection. It was first held on April 22, 1970, and has since grown to include a wide range of events coordinated globally by EarthDay.org, involving over 1 billion people in more than 193 countries.

Earth Day's mission is to diversify, educate, and activate the environmental movement worldwide. The organization works to drive transformative change for people and the planet through a variety of campaigns and initiatives focused on climate action, science and education, people and communities, conservation and restoration, and plastic and pollution.

In terms of sustainability, Earth Day plays a crucial role in raising awareness and mobilizing action towards a more sustainable future. The organization promotes sustainable practices and policies through its various programs and partnerships. It encourages individuals and organizations to take action in reducing their carbon footprint, conserving resources, and advocating for environmental policies.

Earth Day's initiatives often include tree planting, clean-up events, educational workshops, and advocacy for policy changes aimed at reducing environmental impact. The organization also provides resources and tools to help individuals and communities implement sustainable practices in their daily lives.

While Earth Day itself is not a company with traditional sustainability certifications, its impact is measured by the global participation and the positive environmental changes it inspires. The organization's efforts contribute significantly to the global sustainability movement by fostering a culture of environmental responsibility and stewardship.