Today, Twitter launched custom timelines to help users control and organize tweets that appear in a steam. Users can choose the tweets they want to include in their custom timelines programmatically via the API or manually via TweetDeck. For example, an event organizer can curate the tweets related to that event and even embed it on their website.

Custom timelines are public and have their own page on Twitter.com so they can be shared easily. Here are several examples from Twitter of how custom timelines have been tested:

POLITICO is using the new API to organize tweets from policy industry experts in this new Tweet Hub. As the screenshot below shows, tweets are curated into three groups of energy reporters, energy influences and energy lawmakers. Politico has established its own hashtag, #energyinsider, for the hub, but it’s not one of the criteria for inclusion in the timelines. Politico has also turned the hub into a sponsorship opportunity, currently “presented by” Chevron.

The Guardian is hosting a Q&A and will curate the lead question, questions from readers, and answers from journalists into a custom timeline.

Twitter #music has created new timelines that present the very best Tweets from superstars, best songs with tracks you can play right in the Tweet, and the best music Vines. Here is a look at the Best Songs custom timeline. Notice users have the ability to embed this timeline from the link provided in the right column.

Custom timelines are rolling out to all TweetDeck users over the next several days. The new custom timelines API beta will allow users to build timelines based on specific logic or, a la TweetDeck, create tools that help others build their own custom timelines. The API will open to select partners. You can apply here.

The debut of custom timelines should help address the fairly loud complaints that Twitter’s interface is too overwhelming for novice users to easily find the content they are looking for. It also gives broadcasters, publishers and event producers more incentive to incorporate Twitter into their outreach efforts. Until now companies looking to curate tweets around topics and events have had to rely on third-party vendors.

Postscript: Also see our follow-up story, How Twitter Custom Timelines May Boost Twitter’s Reach Into The Web