YaCy (pronounced “ya see”) is a free distributed search engine built on the principles of peer-to-peer (P2P) networks, created by Michael Christen in 2003.

This decentralized approach ensures privacy and eliminates the need for a central server.

[6] Compared to semi-distributed search engines, the YaCy network has a distributed architecture.

[7] YaCy search engine is based on four elements:[8] YaCy uses a combination of techniques for the networking, administration, and maintenance of indexing the search engine, including blacklisting, moderation, and communication with the community.

Here is how YaCy performs these operations: YaCy is available in packages for Linux, Windows, and Macintosh, and also as a Docker image; it can also be installed on other operating systems either by manually building it, or using a tarball.