The official name of the language is Go.

"Golang" is a popular nickname that originated from the official website's domain name, golang.org. The domain was chosen because "go" is a common word, making it difficult to search for online. Using "golang" for the website and for social media hashtags (#golang) made the language much easier to find.

Over time, this nickname became widely used, but the creators and all official documentation refer to the language simply as Go.