The term effective altruism (EA) came from the umbrella name for Giving What We Can (GWWC) and 80,000 Hours (80k).
GWWC started as a giving society with the goal of encouraging people to give 10% of their income on a regular basis to alleviate world poverty founded in 2009.
80,000 Hours was founded in 2011. It aims to provide career advice for young people who want to have a larger social impact through their careers.
The result was the Centre for Effective Altruism (CEA). It was registered as a charity in the UK in 2012. The mission of CEA is to create a global community of people who make helping others a core part of their lives and to do good as effectively as possible.
EA started spreading as a movement with a global community of people who care about doing more to create a positive social impact in this world. EA chapters grew organically, led by people who care deeply about taking actions in their lives for a better world.
Since 2013, CEA has been organising annual EA conferences (known as "EA Global").
There are currently more than 300 chapters around the world. These EA communities come together to promote doing more good, based on evidence and reason.