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Welcome to NCBI
===============
The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.
* [About the NCBI](home/about/) |
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### Popular Resources
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### NCBI News & Blog
* [New Ranks in NCBI Taxonomy: Domain & Realm](https://ncbiinsights.ncbi.nlm.nih.gov/2025/02/27/new-ranks-ncbi-taxonomy/)
27 Feb 2025
As previously announced, NCBI continues to make improvements to our Taxonomy resource. There have been recent updates to the International Code of Nomenclature of Prokaryotes (ICNP) and proposals by the International Committee on Taxonomy of Viruses (ICTV). As a result, NCBI Taxonomy has discontinued the use of rank “superkingdom” to classify organisms into Archaea, Bacteria, Eukaryota, … [Continue reading New Ranks in NCBI Taxonomy: Domain & Realm →](https://ncbiinsights.ncbi.nlm.nih.gov/2025/02/27/new-ranks-ncbi-taxonomy/)
* [New! Introducing the Multiple Comparative Genome Viewer (MCGV) Beta Release](https://ncbiinsights.ncbi.nlm.nih.gov/2025/01/16/new-mcgv-beta-release/)
16 Jan 2025
NLM’s NCBI is excited to introduce the Multiple Comparative Genome Viewer (MCGV), a new tool in active development that allows you to visualize an alignment of multiple eukaryotic genomes. While our existing Comparative Genome Viewer (CGV) allows you to compare pairs of eukaryotic assemblies, the new MCGV tool can help you analyze multiple assemblies in … [Continue reading New! Introducing the Multiple Comparative Genome Viewer (MCGV) Beta Release →](https://ncbiinsights.ncbi.nlm.nih.gov/2025/01/16/new-mcgv-beta-release/)
* [An updated bacterial and archaeal reference genome collection is available!](https://ncbiinsights.ncbi.nlm.nih.gov/2025/01/14/updated-bacterial-and-archaeal-reference-genome-collection-2/)
14 Jan 2025
Download the updated bacterial and archaeal reference genome collection! We built this collection of 21,258 genomes by selecting the “best” genome assembly for each species among the 400,000+ prokaryotic genomes in RefSeq. What’s new? As previously announced, we updated our release process: There is now an incremental process. In addition to quarterly releases, there will … [Continue reading An updated bacterial and archaeal reference genome collection is available! →](https://ncbiinsights.ncbi.nlm.nih.gov/2025/01/14/updated-bacterial-and-archaeal-reference-genome-collection-2/)
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