W3C's Java Server. Jigsaw is W3C's leading-edge Web server platform, providing a sample HTTP 1.1 implementation and a variety of other features on top of an advanced architecture implemented in Java. The W3C Jigsaw Activity statement explains the motivation and future plans in more detail. Jigsaw is an W3C Open Source Project, started May 1996.
A list server (mailing list server) is a program that handles subscription requests for a mailing list and distributes new messages, newsletters, or other postings from the list's members to the entire list of subscribers as they occur or are scheduled.
A proxy Trojan, as the name suggests, is a kind of Trojan malware which creates proxy servers out of infected computers for staging anonymous attacks. Like all Trojans, the proxy is spread disguised as legitimate software downloads and attachments or piggy-backing on legitimate downloads and attachments.
In the client/server programming model, a server program awaits and fulfills requests from client programs, which may be running in the same or other computers. A given application in a computer may function as a client with requests for services from other programs and also as a server of requests from other programs.