Twitter is usually seen as a networking website inundated with people’s thoughts on celebrities, blockbuster films and reality television.

This year however the site has been dominated by the disputed Iranian election, according to Twitter’s annual list of the most used words and phrases. The list, which was released yesterday, highlights the trends and events that have caught the public’s attention. The site has increased in popularity this year, gaining about six million users worldwide according to Nielsen, a market research company.

Analysts said that the site came of age during Iran’s post-election turmoil in June, when opposition activists used Twitter to co-ordinate protests and voice concerns. Because much of the Iranian mobile telephone system was disabled the internet became the key organising medium for the opposition, with websites such as Facebook and Twitter the favourite forums.

Twitter was used because there was no time delay on messages, so information could not be filtered or censored. The moment that a user sends a tweet anyone with an internet connection anywhere in the world can see it. It is also difficult to track individuals so people can stay anonymous if they want to, analysts said.

The US State Department recognised the importance of its role during the protests and even asked Twitter to delay maintenance.

Writing on the company’s blog, Abdur Chowdhury, Twitter’s chief scientist said: “The terms #iranelection, Iran and Tehran were all in the top-21 of Trending Topics, and #iranelection finished in a close second behind the regular weekly favourite #musicmonday.”

The rankings were organised into various categories, including “news events”, “people” and “hashtags” — when users add prefix words with a “#” character in order to group common topics and make them easier for others search for.

Twitter’s rankings reflected use of the site worldwide, and as a result was dominated by American stories and personalities, such as Michael Jackson who died in June and the Adam Lambert, the runner-up in this year’s American Idol.

Figures from the market research firm Nielsen suggest that there are 6 million active users of the site worldwide, with the majority based in the US.

However, Brits are well represented on the list. The Scottish singer Susan Boyle failed to take the main prize again, with the Britain’s Got Talent contestant falling to second place behind Michael Jackson. Wimbledon was the third most popular sports tweet of the year, with Chelsea and Liverpool football teams also finding places in the that top ten list.

News Events

1. #iranelection

2. Swine Flu

3. Gaza

4. Iran

5. Tehran

6. #swineflu

7. AIG

8. #uksnow

9. Earth Hour

10. #inaug09

People

1. Michael Jackson

2. Susan Boyle

3. Adam Lambert

4. Kobe (Bryant)

5. Chris Brown

6. Chuck Norris

7. Joe Wilson

8. Tiger Woods

9. Christian Bale

10. A-Rod (Alex Rodriguez)

Movies

1. Harry Potter

2. New Moon

3. District 9

4. Paranormal Activity

5. Star Trek

6. True Blood

7. Transformers 2

8. Watchmen

9. Slumdog Millionaire

10. G.I. Joe

TV Shows

1. American Idol

2. Glee

3. Teen Choice Awards

4. SNL (Saturday Night Live)

5. Dollhouse

6. Grey’s Anatomy

7. VMAS (Video Music Awards)

8. #bsg (Battlestar Galatica)

9. BET Awards

10. Lost

Sports (Teams, Events, Leagues)

1. Super Bowl

2. Lakers

3. Wimbledon

4. Cavs (Cleveland Cavaliers)

5. Superbowl

6. Chelsea

7. NFL

8. UFC 100

9. Yankees

10. Liverpool

Technology

1. Google Wave

2. Snow Leopard

3. Tweetdeck

4. Windows 7

5. CES

6. Palm Pre

7. Google Latitude

8. #E3

9. #amazonfail

10. Macworld

Hash Tags

1. #musicmonday

2. #iranelection

3. #sxsw

4. #swineflu

5. #nevertrust

6. #mm

7. #rememberwhen

8. #3drunkwords

9. #unacceptable

10. #iwish

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