Search engine giant Google turned 25 on Wednesday.

Marking the special occasion, the company unveiled a special doodle on its homepage.

The doodle shows all the previous logos of the company and ends with the letters ‘oo’ replaced by ’25’ in the word ‘Google’.

Google was founded by Larry Page and Sergey Brin in September 1998, as part of a PhD project. The two ideated the firm in 1995. By 1996, they had reportedly built a search engine, initially called 'BackRub', that used links to determine the importance of individual web pages.