How to know what hashtags are trending on Twitter

Twitter trends are popular words or hashtags used by Twitter users at a particular time. Twitter uses a special algorithm that is not revealed to us yet to monitor hot topics in real time.
If you log in to your Twitter account, you will be able to know what hashtags are now trending in your city or a nearby location. You can also search for any location to view what’s trending there. Alternatively, you can stick to viewing hashtags trending world-wide to have a glimpse of popular topics people are talking about.

Other services you should check out are:
What The Trend
This Website shows you the latest trending hashtags around the world as well as in most of the world’s countries. Click on any location to view the latest hashtags (including Arabic hashtags). It doesn’t stop there though; people are encouraged to explain why a hashtag is trending! Define any hashtag or retweet it by clicking on the buttons. If you click on any hashtag you can read why is it trending and see related tweets.

Trends Map
Log in with your Twitter account to see a real-time tracking of trending hashtags in the world using a gigantic dynamic world map. Zoom in on any location and click on any appearing hashtag to see tweets. If you register for the pro account you will also know where else is it trending and what Twitter users are using this hashtag.

Are you following what happens around you on Twitter? What are the trending hashtags nearby?