Jaiku was a social networking, micro-blogging and lifestreaming service comparable to Twitter. Jaiku was founded in February 2006 by Jyri Engeström and Petteri Koponen from Finland and launched in July of that year. It was purchased by Google on October 9, 2007.

When Jaiku Ltd was an independent company, its head office was in Helsinki.

Jaiku was created in February 2006 by Helsinki-based Jaiku Ltd. The founders of Jaiku chose the name because the posts on Jaiku resemble Japanese haiku. Also, the indigenous Sami people of Finland have traditionally shared stories by singing joiks.

On January 14, 2009, it was announced that Google would be open-sourcing the product but would "no longer actively develop the Jaiku codebase" leaving development to a "passionate volunteer team of Googlers".

On March 12, 2009, Jaiku was re-launched on Google's App Engine platform and on March 13, 2009 the source code to JaikuEngine (the open source equivalent of the jaiku.com codebase) was released.

On October 14, 2011, Google announced they decided to shut down the Jaiku services by January 15, 2012.