The original article used the word pidgin as a metaphor: a simplified shared language can help groups that do not otherwise speak the same language communicate. A multi-protocol messenger offered a similar convenience for people with accounts on different networks.
The idea behind the client
Rather than requiring a separate application for every supported service, Pidgin presented accounts and conversations through one interface. The aim was to simplify communication without pretending that all the external networks were the same service.
The source described that as useful both for work and for keeping in touch with friends and family.
The purple pigeon and the earlier name
Pidgin's pigeon mascot reinforced the communication theme. The article connected the bird with the older idea of a messenger carrying information between people.
Its historical account credited Mark Spencer with beginning the project in 1999, originally as Gaim, and described the later name change in the context of a dispute over the earlier name. These are the origins presented by the source.
The compatibility list in its period
The article named a wide set of services and protocols, including MSN or Windows Live Messenger, OSCAR-based services, XMPP, Gadu-Gadu, IRC, MySpaceIM, GroupWise, SILC, Yahoo, Zephyr, Sametime, QQ, SIP-related chat and Bonjour.
That is a historical list. It does not mean a current installation can sign into every one of those old networks. Services can close, change access methods or remove the protocol an older client relied on.
Plugins and additional features
The source also described extensions for tasks such as file exchange, voice, video and encrypted chat. It named examples from the period to show how a client could be extended beyond basic text conversations.
A plugin's name in an old article is not a reason to install it on a current system. Check the actual project, compatibility and maintenance information before choosing an extension.
Reading the article today
The lasting concept is the separation between a client interface and the external services it connects to. Open-source client code does not ensure that a service provider will keep an old endpoint working.
For project information, use the Pidgin project website. The multi-protocol overview explains the original motivation.