Yahoo Instant Messenger

For the movie database, see Yahoo! Movies, for the mail service, see Yahoo! Mail.
Yahoo! Messenger is an advertisement-supported instant messaging client and associated protocol provided by Yahoo!. Yahoo! Messenger is provided free of charge and can be downloaded and used with a generic "Yahoo! ID" which also allows access to other Yahoo! services, such as Yahoo! Mail, where users can be automatically notified when they receive new email.

Yahoo! also offers PC-PC, PC-Phone and Phone-to-PC service, file transfers, webcam hosting, text messaging service, and chat rooms in various categories.
Yahoo! Messenger was originally launched under the name Yahoo! Pager on 1998-03-09.
In addition to instant messaging features similar to those offered by ICQ, it also offers (on Microsoft Windows) features such as: IMVironments (customizing the look of Instant Message windows, some of which include authorized themes of famous cartoons such as Garfield or Dilbert), address-book integration and Custom Status Messages. It was also the first major IM client to feature BUZZing and music-status. Another recently added feature is customized avatars.


Announcements
On December 5, 2007, Yahoo! Messenger announces the release of Yahoo Messenger for Windows Vista as a Beta Release. It includes transparent Glass Windows and a new skin and GUI for the Windows Sidebar and program.

Also integrated new tabs for going between different chat windows.
On October 29, 2007, Yahoo! Messenger announced the release of Yahoo! Messenger 9 Beta. It features a new and improved interface, new emoticons (also hidden emotions), the integration with Flickr account and a new in-line media player which enables the user to view maps, photos and videos from sites like Yahoo! Video and YouTube right in the IM window.
Yahoo! has announced a partnership with Microsoft to join their instant messaging networks.

This change has taken effect as of 2006-07-13 - Yahoo! Messenger has integrated instant messaging with Windows Live Messenger users, and is fully functional.
British Telecommunications' BT Communicator software is based on Yahoo! Messenger. It is also available for the Mac OS X platform .
Voicemail and file sharing
Yahoo! added voicemail and file sending capabilities to their client.File-sharing of sizes up to 2GB was added.
Plug-ins
As of 8.0, Yahoo! Messenger has added the ability for users to create plug-ins (via the use of the freely available Yahoo! Messenger Plug-in SDK), which are then hosted and showcased on the Yahoo! Plug-in gallery.
Yahoo! Mail integration
Yahoo! plans to integrate Yahoo! Mail Beta and Yahoo! Messenger. Conversations will be archived and stored in the same manner as emails. This allows users to search within their chat logs easily, and to have them centrally stored and accessible from any computer.
Chat
All versions of Yahoo! Messenger have included the ability to access Yahoo! Chat rooms.
On June 19, 2005, with no advance warning, Yahoo! disabled users' ability to create their own chat rooms.

Many regulars in these rooms used the rooms to set up meetings to have sex with children and trade lewd pictures. While it was thought this move came as a result of several advertisers pulling their ads from Yahoo!, a more likely cause was a $10 million lawsuit filed by watchdog groups of internet portals on behalf of a 12-year-old victim of molestation .
Yahoo! has since closed down the chat.yahoo.com site (which is now a redirect to a section of the Yahoo! Messenger page) because the great majority of chat users accessed it through Messenger.

In August of 2007, it began requiring word verification in order to use Yahoo! Chat. Officially, this is to guard against spammers and automated bots, which had been a source of frustration for many chatters (This method has proved highly unsuccessful, as many rooms now have more bots than users).

However, as this also logs users' IP addresses, this feature could presumably be used to monitor against the type of behavior that prevailed in the pedophilia-oriented rooms. The company claims to be still working on a way to allow users to create their own rooms while providing safeguards against abuse.
As of October 2008, Yahoo's inability to control chat bots and spammers continues to be a major issue.Recently, it has switched from DHTML to Adobe Flash in coding.
URI scheme
Yahoo! Messenger's installation process automatically installs an extra URI scheme ("protocol") handler into some web browsers, so that URIs beginning "ymsgr:" can open a new Yahoo! Messenger window with specified parameters. This is similar in function to the mailto: URI scheme, which creates a new e-mail message using the system's default mail program.

For instance, a web page might include a link like the following in its HTML source to open a window for sending a message to the YIM user notarealuser:
<a href="ymsgr:sendim?notarealuser">Send Message</a>
To specify a message body, the m parameter is used, so that the link location might look like this:
ymsgr:sendim?notarealuser&m=This+is+my+message
* ymsgr:sendim? Example: ymsgr:sendim?myid
* ymsgr:addfriend? Example: ymsgr:addfriend?myid
* ymsgr:sendfile? Example: ymsgr:sendfile?myid
* ymsgr:call? Example: ymsgr:call?1-800-555-7654
* ymsgr:callPhone? Example: ymsgr:callPhone?1-800-555-7654
* YMSGR:chat? <"opens chat room list" Note: bigblueball does not like ? at the end of a link!
* ymsgr:im? <Opens "send an im window" Note: bigblueball does not like ? at the end of a link!
* ymsgr:getimv?doodle
* ymsgr:getimv?yfighter

Offline messaging
Offline messaging, a feature long offered by Yahoo!, allows online users to send messages to their contacts, even if said contacts are not signed in at the time. The sender's offline contacts will receive these messages when they next go online.
Interoperability
On October 13, 2005, Yahoo! and Microsoft announced plans to introduce interoperability between their two messengers, creating the second largest real time communications service userbase worldwide: 40 percent of all users (AIM currently holds 56 percent).

The announcement comes after years of 3rd party interoperability success (most notably, Trillian, Pidgin) and criticisms that the major real time communications services were locking their networks. This allows, for Yahoo! and Windows Live Messenger users to chat to each other without the need to create an account on the other service, provided both contacts use the latest versions of the clients.

For now, it's impossible to talk using the voice service among both messengers.
Games
There are various games and applications available that can be accessed via the conversation window by clicking the games icon and challenging your current contact. It requires Java to work.
Main process
The Windows version of Yahoo! Messenger previously used ypager.exe as the name of the instance of the client.It was changed to yahoomessenger.exe since the beta of version 7.5.0.
Malware
Yahoo! Messenger (along with other networks such as Windows Live Messenger and AOL Instant Messenger) is often used as a conduit or "vector" for delivering malicious software such as spyware, viruses, worms, and trojans to unsuspecting computer users. The three methods used by hackers to deliver malware over the IM vector are (1) sending a file transfer with a virus-infected file, (2) delivering a message with socially engineered content containing a web address (URL) containing active malicious code and (3) sending specially crafted messages exploiting security vulnerabilities in the client software.

A socially engineered message is one that is written in a friendly, informal manner, that could easily be mistaken as coming from a friend. Upon clicking the web address, the recipient is connected to a website containing active content, which is immediately downloaded to the recipient's computer.

When the message is sent to all contacts, the cycle starts again, as each contact believes they are receiving a message from a trusted friend. In this manner, IM-borne malware is capable of propagating very rapidly through company and external networks.
Worms and viruses are discovered on a regular basis by security companies, particularly by the three companies with IM-specific security products, Akonix Systems, FaceTime Communications, and Symantec.

According to IM security researchers at Akonix, the number of new threats identified each month is 30 to 35, with a high of 88 in October, 2006.
SPIM
Yahoo! Messenger users are subject to unsolicited messages (SPIM) and the problem remains unresolved. Blogs and websites addressing this issue are supportive of the chat environment, and writers genuinely want to continue using the service, yet express frustration about Yahoo's apparent failure to address spam and other related problems.