Astrophysics Data System This NASA-funded project's main resource is an abstract service to provide pointers to astronomical data catalogs and archives. Includes data from space missions. (Web-free access)

Contributions of 20th Century Women to Physics Profiles 86 women from various subfields of physics.

Flash Animation for Physics Includes more than 80 Flash animations from various areas of physics.

HCI Bibliography A bibliographic database from Human-Computer Interaction Resources promotes awareness of the current state of human characteristics combined with computer development and functions. (Web-free access)

Light and Matter Physics and Astronomy Resources A series of online introductory physics textbooks.

NASA Technical Reports Server Provides access to the NTRS's significant technical materials, including articles, conference and research reports, and various other online documents.

Official String Theory Website An authoritative and interesting-to-peruse site which covers both basic and advanced aspects of string theory.

Physics Hypertextbook A work in progress on key concepts in physics.

Physics 2000 Key concepts of modern physics are provided in interactive modules on this well-organized site. (Web-free access)

Physlink A comprehensive physics and astronomy site which includes educational, research and reference information and material. (Web-free access)

Science.gov Provides science info and data and results of scientific research; also a gateway to more than 1800 science-related websites.