One thing's clear here -- if you want to communicate via IM, the widest audience is available by using AIM.

This article marks the first in an occasional series of reviews on the public IM networks and the clients that access them. We'll examine the clients from a business perspective, and let you know which work well as a stop-gap measure for your professional (and personal) IM needs -- especially important for people whose employers don't yet have or endorse IM.

This week, we examine the stand-alone AIM application that doesn't require a user to log into AOL's online service to use. Specifically, we're looking at the 4.7 version of AIM for Windows.

The best news is that users don't need to have an AOL account to use AIM. The client combines AOL's Buddy List and Instant Message features first launched via the AOL service, and is the de-facto standard by which all other public IM programs -- and many enterprise IM systems as well -- are judged and designed.

Being a consumer product, AIM has many features targeted at that market, including Buddy Icons, AIM Talk for live online conversations, and ways to share pictures, photos and sounds. Another feature called IM Greetings lets people use AIM to send instant online greetings for birthdays, holidays, graduations, anniversaries, and other special occasions.

The price of "free," though, comes at a cost. You're subjected to small banner-type ads at the top of the Buddy List window. You're also asked about to set up a bunch of customized features (stock quotes, news and the like) that sound fine for consumers, but are probably not necessary in the business environment. Of course, you don't have to activate any of these features to use AIM.

Probably the biggest pain is the "AIM Today" window that pops up whenever the AIM program is started. It contains all kinds of information ideal for consumers ("find people on IM;" "topics" like career, entertainment and Life & Love; and special AOL-developed features that, of course, are ad-supported). Thankfully, this "option" can be disabled as well.

About the only feature AOL targets specifically at business users is HTTP proxy support, which makes it easier for users to connect to the AIM service from work and corporate environments that are behind network firewalls. In its defense, though, AOL never said AIM was ideal for, or even supposed to be used in, a corporate environment.

In terms of simply keeping track of buddies and hosting one-on-one conversations, though, the AIM client can't be beat. All you'd probably want to do is shut off all of the consumer-type customization features.

In short, if you want to reach the largest IM audience and you don't mind a plethora of consumer-related features, then AIM is for you. Beware, though -- many features you'd want in an IM client, like chat logging/auditing and encryption, are not available "out of the box" in AIM. You might want to treat any and all conversations you have in AIM like ones you have at a bar on a Friday or Saturday night, in that you may not remember everything that's said and anyone can hear you talk.

Of course, there are add-on applications from companies like FaceTime Communications, which provides services like auditing, and PresenceWorks, which provides IM presence information.

Not tested for this review are the AOL Messenger application used with AOL clients like 7.0, and the Web-based AIM Express. A version 4.8 of the AIM client is out, but we did not look at that version since it is in beta. New features for AIM 4.8 include a mobile indicator that displays a special icon for buddies that are using certain wireless devices, as well as a new "send to" extension and a special alerts option.

Stroud's CWS Apps, a sister site of InstantMessagingPlanet, did examine the 4.8 beta of AIM and gave it five stars (full story).

Next time, we'll look at a client that can access all of the major IM nets -- AIM, ICQ, MSN and Yahoo, as well as IRC.

Bob Woods is the managing editor of InstantMessagingPlanet.