In this article, I'll limit myself to illustrating rather than defining. They do not, by themselves, constitute a complete application. Instead, they form one by working in conjunction with an agent host and other agents. In many ways, agents are of the same scope as applets. Small and of limited functionality on their own.
Agent technology is significant because of the sustained commercial interest surrounding it.
Agent technology may not have hit prime time quite yet, but it does seem to be gathering its share of investment money. Take a gander at the Resources section for a host of other companies engaged in agent technology development. Agent technology is also interesting for its potential to solve some nagging productivity problems that pester almost all modern computer users. Agent technology solves, or promises to solve, several problems on different fronts. A transaction or query between a client and the server may require many round trips over the wire to complete.