SAN FRANCISCO – As part of an ongoing effort to improve its user experience, Internet company AOL Inc. is letting users of its AIM instant-messaging service chat with friends on Facebook.

AOL said Wednesday that a new version of AIM connects with the instant-messaging function on Facebook's Web site, letting AIM users communicate with friends who are logged on to the social network and available to chat.

Once an AIM user downloads the new software and links it with their Facebook profile, their buddy list will include a list of online Facebook friends.

Excluding mobile, AIM has about 17 million users — a fraction of the more than 400 million on Facebook. It launched a "lifestreaming" feature last year that let users see friends' latest posts on social sites like Facebook and Twitter.