Oct 27, 2010 10:20 GMT  ·  By

If you're online, you've heard of Twitter, but the company is still rather small, compared to other rising stars of the social web. The company just announced that it now has 300 employees. That may not be a hugely impressive figure, but it's 50 percent more than it had in the middle of the summer.

"We just hired our 300th full-time employee. Wowza! cc: @JoinTheFlock," Twitter tweeted.

Twitter has been growing fast for the past few years and especially in 2010. The company had just announced the 200 employee mark last June. Previously, Twitter announced its 140th hire in February this year.

Twitter had used the 300 employees' number earlier this month, but at the time it meant interns and contractors as well. Now Twitter has 300 full-time employees.

The company is also looking to move out of its offices in the trendy SoMa neighborhood of San Francisco into a bigger facility, though probably close by.

Twitter has spent just one year in its new offices which seemed particularly spacious in November 2009 when it moved in. Just one year later, it's no longer enough to house the growing company.

Twitter started out 2009 with just 22 employees. Right about that time, the service went from a trendy tool with the hipster and geek crowd to a global phenomenon.

The company has been on a hiring bend since then and still has more than 30 open positions at the company in most departments.

Still, it pales in comparison to much larger companies like Facebook which has about 1,700 employees. Granted, Facebook has more than 500 million users, while Twitter just over 150 million.

Others have grown even faster. Zynga, the social gaming powerhouse, has over 1,200 employees right now and is still growing. Groupon is getting close to 1,000.