users from malicious sites, and will use it to track clicks on links within tweets. Having used the services of third parties TinyURL and bit.ly, Twitter began experimenting with its own URL shortening service for private messages in March 2010 using the twt.tl domain, before it purchased the t.co domain. On June 7, 2011, Twitter announced that it was rolling out the feature. Image sharing On June 1, 2011, Twitter announced its own integrated photo-sharing service that enables users to upload a photo and attach it to a Tweet right from Twitter.com. Users now also have the ability to add pictures to Twitter's search by adding hashtags to the tweet. Twitter also plans to provide photo galleries designed to gather and syndicate all photos that a user has uploaded on Twitter and third-party services such as TwitPic. On March 29, 2016, Twitter introduced the ability to add a caption of up to 480 characters to each image attached to a tweet, accessible via screen reading software or by hovering the mouse above a picture inside TweetDeck. In April 2022, Twitter made the ability to add and view captions globally available. Descriptions can be added to any uploaded image with a limit of 1000 characters. Images that have a description will feature a badge that says ALT in the bottom left corner, which will bring up the description when clicked. Polls In 2015, Twitter began to roll out the ability to attach poll questions to tweets. Polls are open for up to 7 days, and voters are not personally identified. Initially, polls could have only two options with a maximum of twenty characters per option. Later, the ability to add four options with up to 25 characters per option, was added. Non-tweet content Streaming video In 2016, Twitter began to place a larger focus on live streaming video programming, hosting various events including streams of the Republican and Democratic conventions during the U.S. presidential campaign as part of a partnership with CBS News, Dreamhack and ESL esports events, and winning a bid for non-exclusive streaming rights to ten NFL Thursday Night Football games in the 2016 season. During an event in New York in May 2017, Twitter announced that it planned to construct a 24-hour streaming video channel hosted within the service, featuring content from various partners. CEO Jack Dorsey stated that the digital video strategy was part of a goal