SAN FRANCISCO - Twitter has redesigned its short messaging service to make it simpler, faster and more personal.

The changes were released Thursday in updates to Twitter's applications for smartphones and tablet computers. Visitors to Twitter's website should start seeing the new look during the next few weeks.

Twitter revamped the service to address one of its biggest challenges. Although a lot of people generally know what Twitter is, many still don't understand how to use the service and its various tools.

With the changes, it will be easier to find people and companies with Twitter profiles. All it will take is typing an "at" symbol in front of a user's handle.

Profile pages are also being expanded so individuals and companies can showcase more information about themselves in text, photos and video.