If you're like a lot of people who have been on the internet for a long time you use the Standard chat Clients, the one's that have been around for years.
These are the following:

Windows Live Messenger:
AKA : MSN
About: MSN as many people still call it is the one of the oldsest and most well known means of Chat on the Internet. Most likely a primative version of this old reliable is pre-installed on your computer if you are a windows user.
There are no specific benefits to MSN. It does what it says on the tin. You chat with people you know, most likely via your account with Hotmail or Windows live. The sort of accounts and email you have had for years, maybe even for over a decade at this stage. Little has changed, and some of the friends may have long gone, but WLM/MSN still stay's similar and in everyone's hearts and minds.
Over the years newer versions have brought, games, Video and voice chat, Nudge's and improved Smiley's / Emoticon's but in essence it has never really changed and that's why it's still popular. And also available on most Smart phones and for Some 3G phone's via a java application that can be downloaded from your network provider's mobile store or via searching for Windows live messenger in your phones browser.
Download here.

AIM, or AOL Instant Messenger.
This old school messenger is one of the most popular Service's for American's, because of it's Link to AOL, a old large scale provider of specific internet service's in the early days of the world wide web.
AIM, the last time i used it, was pretty basic, and it has recently caught up with the times.
AIM now supports Twitter and Facebook integration via a Lifestream. This Lifestream Aggregate's what's happening with your AIM contacts and on your Twitter and Facebook Profile's. A pretty familiar site on modern chat clients but when it's added to such an Old messenger it provides new life and a boost for the messenger.
Download here.

Yahoo Messenger.
The messenger service of Yahoo. Not being a Yahoo user i actually don't have much experiance with Yahoo. But it is a long time classic and competitor to MSN.
The Modern Yahoo Messenger still has a lot of the old features, Chat, Emoticon's, Yahoo Chat rooms. But it also has Video and Voice calling over the internet to Yahoo Messenger and it's Mobile Application for Free. SMS message's over the internet to your contcacts, for free. And Plug-ins for added feature's such as Twitter applications, games and Yahoo related products.
Download here.
Skype, is nowadays synonymous with International phone and video calls over the computer, at a low cost, the same way google is with Search. So much so it can even be used as a verb, if you're so inclined.
Skype is so well known that i barely have to talk about it. But if you did want to use it, all you have to do is download it, set up an account and you're free to chat. That is of course only to other people using Skype.
If you want to really open skype up and call people, you have to pay a small fee each time you do. But if you use it frequently as an alternative to a phone to call anyone, or call overseas it can save you a fortune.
It is also available on Smartphones, The INQ line of phone's via 3 Mobile in Ireland, The UK and Australia and there is also Skype specific Products such as Headsets, web cams and even a Skype phone, that only use's skype, funnily enough.
Download here.
There is also new comers on the block when it come's to how people chat online and from their desktops.

GOOGLE Talk/ Chat
Google Talk is everywhere there is a google Product. Embedded in your GMail and available as an added on to your Calendar, To Do list, Documents, Google Wave and as a key part of the Google Android Smart Phone's. Google Talk also feature's as the native chat on Google's Social Networking Site Orkut. It can even be added to Google Desktop, a google search for your Windows computer.
(It is called Google Talk but it's own label within GMail says Chat, so it can be confusing)
Google Talk for a long time was basic, but handy. All your email contacts are automatically in your Chat Contacts. If they have Gmail it's a simple few clicks and they can also be on Google Chat.
Google also provides a Desktop client that you can download and use to check your GMail account at the same time as keeping in touch with all your Email contacts, business or personal.
As Gmail and other google products evolve so does their Chat client and in the past year it has included Video chat and other feature's that are bog standard on other clients.
Google Chat is fast, simple and found almost everywhere google is. If you use google's large school of products, then you have probably have a google account. If you have a google account you have access to Google Chat. So why not give it a try?
Download the Desktop version Here.
And like 350 million other people, if you're on Facebook you have facebook Chat.

Facebook, the super huge Social Networking site is well known at this stage. and If you're not Liking status updates and posts, or posting on a friends wall, or even using the Mail Inbox, you're going to be using the Facebook Native Chat client.
This simple chat client sits at the bottom of the page and tell's you who is online. Usually this is some old school friend you want to avoid, or a stalker ex, but if your real friends are online, you can chat to them.
Facebook Chat is not without it's Hiccups. Sometimes message's won't send, sometimes it won't even appear at all. Sometimes it's so infuriatingly absent or awful that you just can't be bothered at all. But it's always there as a means of talking privately on the worlds most popular Social Networking Website.

Twitter.
You may not think of this latest craze as a means of talking to someone but it is. Albeit with a limit of 140 characters.
You may find it hard to say something useful in 140 characters but you can have small conversations with fellow Tweeters if you so wish. Just click reply on their tweets, or physically type @TheirScreenName in your tweet and it will show up in their @ replies or in their stream if they follow you.
There is also Direct Message's or DM's if you want to keep it really private. Unfortunately, and for some unknown reason this is also limited by the 140 character limit.
Twitter.com Itself isn't very good at tracking such @ reply conversations, but 3rd party service's such as Tweet Deck, Yoono, Brizzly and Digsby do, in their own unique ways.
www.twitter.com

Lost Cause: You may not know about it, but Myspace also has a chat client of it's own.
It works on the website itself and via a Desktop client. It also has Skype intigration. If you use Myspace, then it's for you. But Myspace is increasingly a niche website for teenager's, Peaodophile's and Music lovers. The more it slips away from the mainstream public the less likely people are to use it for Social Networking, or even chatting with friends.
You can find myspace IM, here.
What you may not of heard of....
IMVU:
IMVU is a 3D based Instant Messenger where you chat via your on Screen Avatar that you customise yourself. You can do what every you like to the appearance of your avatar and you can buy more advanced feature's and personal items if you want to.
IMVU is a very specific niche chat client that require's a lot more attention than most and is really in a world of it's own, a world not to dissimilar to Second life and other similar websites.
IMVU sort of act's like a chat room as well, in that multiple Avatar's can meet at varrious virtual locations.
It also has a meet a random person feature, if you want to use it.
Download here...
If you chat all the time and want to chat to people from all over the place but don't want the clutter, than you have several options available to you.

Ebuddy is a web based Chat client that connects to almost every service you can think of. It opens in an additional window of your internet browser and is very handy when you are not at your own computer, such as at work, in school/college or in a library with computer access.
Vist Ebuddy here.

Pidgin is simple enough service that allows you to connect to all the well know chat clients and a few others. It's main aim is only chat so just expect Text and Video calls from this service.
Download the desktop client here.

Digsby.
Digsby aims to be the Multiple client chat application to beat them all. This rather large tool can not only chat on WLM/MSN, Google Chat, Facebook Chat, AIM, Yahoo and others, it also has Email Inbox notifiers, Facebook, Twitter and the ability to Link and organise all your Contact's together under one Icon in your contact list.
So if a friend is on Facebook and Another service at the same time, you can choose where you want to talk to them from. And Digsby will show you where with a little icon within their picture. It will also allow multiple chat's to occur within the same Instant Messenger Window, even between your contacts.
Digsby is a formidable and strong multiple Chat client that is worth checking out for the die hard chat user.
Download here.

Yoono Started out as an Add-on to Firefox.
As an add-on it's pretty good at Following updates on Facebook and Twitter.
In the past year it also introduced a Desktop client and more feature's, inculding Google Chat, Window's live messenger and AIM.
So check it out here, to get either the add-on or the desktop application, Yoono.
