PlasmoDB is a functional genomic database for Plasmodium species, providing resources for data analysis and visualization at the gene or genome-wide level. It is part of the EuPathDB Bioinformatics Resource Center. The latest release, PlasmoDB 5.5, includes data from eight Plasmodium species, including fully sequenced and annotated genomes. It contains various data types such as annotated genomes, transcription evidence, proteomics evidence, protein function evidence, population biology, and evolution. Users can query data through a grid or dropdown menus and combine results on the query history page. Search results can be downloaded with associated functional data, and registered users can store their query history for future retrieval. PlasmoDB provides data on transcript expression, including microarray data, expressed sequence tags (ESTs), and serial analysis of gene expression (SAGE). It also includes protein expression evidence from various life stages and population biology evidence for P. falciparum. Functional data types include protein-protein interaction evidence, Genome Ontology (GO) annotations, and InterPro domain annotations for multiple Plasmodium species. Enzyme Commission (EC) number annotations and metabolic pathway assignments are also available. Subcellular localization of proteins is provided through signal peptide and transmembrane domain predictions. Users can perform searches for specific genes or ask questions using the database. They can combine results using operations such as 'and', 'or', and 'not'. PlasmoDB also allows users to refine results by intersecting or subtracting query results. The database is expected to continue expanding its data content and tools to meet user needs. Future directions include incorporating new data sets and a new user interface with a workflow-based search strategy. PlasmoDB is funded by the National Institute of Allergy and Infectious Diseases and is part of an NIH/NIAID funded Bioinformatics Resource Center. It is a valuable resource for researchers studying malaria parasites.PlasmoDB is a functional genomic database for Plasmodium species, providing resources for data analysis and visualization at the gene or genome-wide level. It is part of the EuPathDB Bioinformatics Resource Center. The latest release, PlasmoDB 5.5, includes data from eight Plasmodium species, including fully sequenced and annotated genomes. It contains various data types such as annotated genomes, transcription evidence, proteomics evidence, protein function evidence, population biology, and evolution. Users can query data through a grid or dropdown menus and combine results on the query history page. Search results can be downloaded with associated functional data, and registered users can store their query history for future retrieval. PlasmoDB provides data on transcript expression, including microarray data, expressed sequence tags (ESTs), and serial analysis of gene expression (SAGE). It also includes protein expression evidence from various life stages and population biology evidence for P. falciparum. Functional data types include protein-protein interaction evidence, Genome Ontology (GO) annotations, and InterPro domain annotations for multiple Plasmodium species. Enzyme Commission (EC) number annotations and metabolic pathway assignments are also available. Subcellular localization of proteins is provided through signal peptide and transmembrane domain predictions. Users can perform searches for specific genes or ask questions using the database. They can combine results using operations such as 'and', 'or', and 'not'. PlasmoDB also allows users to refine results by intersecting or subtracting query results. The database is expected to continue expanding its data content and tools to meet user needs. Future directions include incorporating new data sets and a new user interface with a workflow-based search strategy. PlasmoDB is funded by the National Institute of Allergy and Infectious Diseases and is part of an NIH/NIAID funded Bioinformatics Resource Center. It is a valuable resource for researchers studying malaria parasites.