The ability to follow trends is handy, especially for web publishers and/or web marketers. Having an idea about what people are saying and/or searching for in the web is valuable as it is the key to running a successful website and there are a few websites and services that helps you in tracking the trends on the web.

Google Trends: Google Trends plays a major role in gauging the trends in the web.  Google Trends displays the major trends happening in the web through a graphical display. It also displays regional and linguistic features along with it. Plus its “Hot Topics” and “Hot Searches” and the recently integrated of real time search feature makes Google Trends one of the standard tools fo checking web trends.

Hashtags: For the visually oriented Twitter user, Hashtags is a great way to keep track of the latest trends in Twitter. With a simple mous-over, the users can see graphs on hashtag, besides seeing the latest and the most popular hashtags.

Monitter: As the name might suggest, this service helps you to monitor the latest things that are trending in Twitter. Monitter is simple to use. Just type in your keywords and it will display the relevant Tweets in real-time. The display is cool enough to jazz up your searching experience as well.

Sideline: This is a Twitter tracker from Yahoo and it is probably the best of the lot in terms of Twitter trends tracking. The app has an eecellent clean, uncluttered interface. You need to download this as a desktop application. Sideline has real nifty features like advanced search query builder, custom search groups, automatic refreshing of defined search queries and a new Influencer tool which is still in a pretty beta stage, but is supposed to distinguish between smart and non-smart users.

TweetMeme: While tracking a trend on Twitter sometimes you need to filter the tweets a bit to stop some of the noise caused by a lot of tweets.  TweetMeme helps here by analyzing the links into categories, subcategories and channels to deliver the most popular links to you.

PicFog: If you are someone who likes to follow a trend through image updates rather than texts, PicFog might just be the service you are looking for. Through PickFog you can see the latest images, along with the number of tweets on them to see how something is shaping up in the web.  PicFog streams in real-time images from Twitter, Twitpic , Twitgoo and Yfrog. However, the interface is slightly messy and it sometimes does throw up some objectionable images.