AmiGO is a web application designed to facilitate the querying, browsing, and visualizing of ontologies and gene product annotations. Developed by the Gene Ontology (GO) Consortium, AmiGO is available online at the GO website and can also be downloaded for local use. The application provides detailed information on terms and gene products, including synonyms, definitions, and evidence codes. Key features include a BLAST search, Term Enrichment tool, GO Slimmer for reducing annotations to high-level terms, and the GO Online SQL Environment (GOOSE) for SQL queries. AmiGO is built using Perl and is open-source, ensuring flexibility and accessibility. Future developments focus on integrating reference genome data, enhancing ontology visualizations, and exploring community-driven annotation through wiki-style software.AmiGO is a web application designed to facilitate the querying, browsing, and visualizing of ontologies and gene product annotations. Developed by the Gene Ontology (GO) Consortium, AmiGO is available online at the GO website and can also be downloaded for local use. The application provides detailed information on terms and gene products, including synonyms, definitions, and evidence codes. Key features include a BLAST search, Term Enrichment tool, GO Slimmer for reducing annotations to high-level terms, and the GO Online SQL Environment (GOOSE) for SQL queries. AmiGO is built using Perl and is open-source, ensuring flexibility and accessibility. Future developments focus on integrating reference genome data, enhancing ontology visualizations, and exploring community-driven annotation through wiki-style software.