ArXiv Front: GR Group Theory  
   Group theory section of the mathematics e-print arXiv.
   http://front.math.ucdavis.edu/math.GR

Group Pub Forum Home Page  
   These are the community pages for Group Theory, the mathematics of symmetry. Group Theory is a branch of algebra, but has strong connections with almost all parts of mathematics.
   http://www.bath.ac.uk/~masgcs/gpf.html

Topological Methods in Group Theory  
   Table of contents only; draft chapters can be downloaded by arrangement.
   http://www.math.binghamton.edu/ross/contents.html

Coxeter/Weyl Tutorial  
   A Tutorial Introduction to the Coxeter and Weyl Packages, a pair of Maple packages for working with root systems, finite Coxeter groups and Weyl characters
   http://www.math.lsa.umich.edu/~jrs/coxtut.html

Symmetry Groups in Maple V  
   A worksheet by W.D. Joyner.
   http://web.usna.navy.mil/~wdj/symm_gp.html

International Society for Group Theory in Cognitive Science  
   Group theory in: Robotics, Problem-Solving, Planning, Learning, Language, Perception, Art, Design, Engineering, Manufacturing, Epistemology, Measurement, Computation, Ne
   http://www.rci.rutgers.edu/~mleyton/GT.htm

Mod-2 Cohomology of 2-Groups  
   Computer calculation of the mod-2 cohomology of groups of order 8, 16, 32 and 64.
   http://www.math.uga.edu/~jfc/groups/cohomology.html

GAP - Groups, Algorithms and Programming  
   GAP is a free system for computational discrete algebra.
   http://www.gap-system.org/

The Moonshine Page  
   Bibliography, meetings.
   http://cicma.mathstat.concordia.ca/faculty/cummins/moonshine.html

Permutation Group Problems  
   Compiled by Peter Cameron.
   http://www.maths.qmw.ac.uk/~pjc/pgprob.html

Semigroup Theory  
   Directory of home pages and conferences maintained at Southampton University.
   http://www.maths.soton.ac.uk/semigroups/homepage.html

Permutation Groups Resources  
   Web-based resources for permutation groups and related areas in group theory and combinatorics.
   http://www.maths.qmw.ac.uk/~pjc/permgps/

The North British Quantum Groups Collective  
   The North British Quantum Groups Collective meets regularly to discuss research in quantum groups, with the aim of disseminating recent results and exchanging ideas and information on the subject.
   http://www.mcs.le.ac.uk/~rjm25/qg.html

Introduction to Group Theory  
   A fairly easy to understand tutorial. Fourteen sections, including groups, Cayley tables, subgroups, cosets, Lagrange's theorem, cyclic groups and subgroups, permutations, and Rubik's cube.
   http://members.tripod.com/dogschool/

Papers by R. E. Borcherds  
   Including proof of the Moonshine Conjecture (TeX, DVI, PDF).
   http://math.berkeley.edu/~reb/papers/

Trinomials with Interesting Galois Groups  
   Parametrisation of trinomials with Galois groups contained in the simple group G168.
   http://www.math.harvard.edu/~elkies/trinomial.html

Binary Coordinate Systems  
   Article by Steven H. Cullinane. Defines "Cartesian" coordinate systems for small finite geometries over the two-element field, and discusses geometrically simple generators for affine group actions.
   http://m759.freeservers.com/coord.html

PARGAP  
   Parallel GAP/MPI (ParGAP/MPI), a share package for GAP. UNIX (or Cygwin/Windows). Download source and documentation by FTP.
   http://www.ccs.neu.edu/home/gene/pargap.html

Open Problems in Group Theory  
   Part of the Magnus project. Contains over 150 problems in group theory, both well known and relatively new.
   http://zebra.sci.ccny.cuny.edu/web/nygtc/problems/

Broue's Abelian Defect Group Conjecture  
   A record of which groups and blocks have been proved to satisfy the conjecture, maintained by Jeremy Rickard.
   http://www.maths.bris.ac.uk/~majcr/adgc/adgc.html

Symmetric Presentations  
   Some presentations of groups (symmetric or otherwise).
   http://web.mat.bham.ac.uk/J.N.Bray/res.html

Group Action Forum  
   Association for the study of the theory of transformation groups and related topics. Members, news, events, publications.
   http://gaf.astagor.net/

New York Group Theory Cooperative  
   Software (Magnus), preprints, meetings, links. Magnus - a graphically-oriented system for computational group theory - allows one to explore and experiment with abstract groups without the need for learning yet another programming language. Magnus is fr
   http://zebra.sci.ccny.cuny.edu/web/

Symmetry  
   The main point group symmetries of interest to defect physics by operation (reflection, rotations etc) and classification (trigonal, and cubic). Most point groups also have the associated character table on-line.
   http://newton.ex.ac.uk/research/qsystems/people/goss/symmetry/index.html

The World of Groups  
   Part of the World Wide Algebra project. Open problems in combinatorial group theory, a list of personal web pages, conferences and seminars, and useful links.
   http://www.cs.gc.cuny.edu/~cryptlab/gworld/gworld.html