Galaxy Zoo - Interactive project that allows the user to participate in a large-scale project of galaxy research: classifying millions of galaxies found in the Sloan Digital Sky Survey.

Andromeda Galaxy - Information about the Andromeda Galaxy with descriptions and pictures.

Arp's Atlas of Peculiar Galaxies - Information about Halton Arp's 1966 "Atlas of Peculiar Galaxies," aimed chiefly at amateur astronomers. Includes summary data, observing tips, and images. By Dennis Webb.

BBC Science and Nature: Galaxy Guide - Provides an introduction to the classification of galaxies into spiral, barred spiral, elliptical, irregular, lenticular and radio galaxies.

DIRECT Project Homepage - Determining the distances to nearby galaxies.

Dust in Spiral Galaxies - HST and ISO Results.

European Network: The Formation and Evolution of Galaxies - Purpose is to understand the creation of galaxies and the universe has evolved. Plans to study distant galaxies at optical, infrared, and radio frequencies.

Faulkes Telescope Educational Guide - Galaxies - Some useful information about the formation of galaxies.

Galaxies - NASA Windows to the Universe. Includes illustrations and introductory information about a variety of galaxies.

Galaxies - Includes a set of notes by Nick Strobel. Topics include the structure of the Milky Way, the characteristics of other galaxies, and finding distances to other galaxies.

Galaxies - Many selected links to websites dedicated to galaxies.

Galaxies - Galaxies with their descriptions.

Galaxy - Wikipedia - Contains information of the types, dynamics, observations, and formation of galaxies.

Galaxy Collisions - A review article for non-specialists.

Galaxy Evolution Explorer - Contains information about the growth of various galaxies. Also includes images, news, and a glossary.

Galaxy Formation & Evolution Lecture Notes - Lectures given in 2006 by Julien Devriendt at Oxford University, which include an introduction to galactic dynamics and a primer on hierarchical galaxy formation.

Galaxy Morphological Classification - Wikipedia article about the several schemes in use by which galaxies can be classified.

Globular Clusters in the Andromeda Galaxy - Data, observation notes, and more about globular clusters within the galaxy.

High Redshift Supernova Search - Project at Lawrence Berkeley National Lab to search for supernovas in very remote galaxies. This provides an accurate means of measuring the distances to remote galaxies and thereby determining the age of the universe.

Lecture 27: Spirals and Ellipticals and Irregulars - Classifications, properties, and structures and dynamics.

M31: The Andromeda Galaxy - Includes a catalog of globular clusters, photos, and brief description.

The Messier Catalog - Provides images of and information on Messier objects.

Optical and Interpretative Astronomy Group - Research group at the Ludwig-Maximilians-University Observatory studying the structure and evolution of galaxies, especially stellar dynamics, stellar populations and galaxy formation from the point of view of optical and near-infrared astronomy.

Review Articles about Galaxies - A collection of hundreds of review articles. Topics covered include normal, peculiar and interacting galaxies, as well as galaxy evolution and galaxy clusters. Part of Caltech's "LEVEL 5" knowledgebase of extragalactic astronomy and cosmology.

Skywalker Viewing Tool - Java-based viewing tool that allows the user to view galaxy surveys such as the Hubble Deep Field, using their browser.

The Small Magellanic Cloud, SMC - Gives mathematical measurements relating this galaxy that orbits the Milky Way. Includes history about first known discoveries and links to photo galleries.

Spiral Galaxies - Spiral galaxies with short descriptions and photos.

UMass High Energy Astrophysics Group - Research group primarily interested in high energy activities in galaxies, particularly the interplay between massive stars and the interstellar medium.