The Genome Browser provides a visual display of chromosomal informaiton, allowing zoom and scroll over chromosomal and DNA sequence, showing the work of annotators worldwide. Other tools included on the site provide other means of accessing genomic and proteomic data: Gene Sorter shows expression, homology and other information on groups of genes that can be related in many ways; Blat quickly maps your sequence to the genome; Table Browser provides convenient access to the underlying database; VisiGene lets you browse through a large collection of in situ mouse and frog images to examine expression patterns. The site contains the reference sequence and working draft assemblies for a large collection of genomes. It also provides a portal to the ENCODE genome annotation project.

http://genome.ucsc.edu/