Online technical databases


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The fundamental principles by which Wikipedia operates are the Five pillars. The Wikipedia community has developed many policies and guidelines to improve the encyclopedia; however, it is not a formal requirement to be familiar with them before contributing.


MatWeb's searchable database of material properties includes data sheets of thermoplastic and thermoset polymers such as ABS, nylon, polycarbonate, polyester, polyethylene and polypropylene; metals such as aluminum, cobalt, copper, lead, magnesium, nickel, steel, superalloys, titanium and zinc alloys; ceramics; plus semiconductors, fibers, and other engineering materials.

We have over 83,000 materials in our database, and we are continually adding to that total to provide you with the most comprehensive free source of material property data on the web. For your convenience, MatWeb also has several Converters and Calculators that make common engineering tasks available at the click of a button. MatWeb is a work in progress. We are continually striving to find better ways to serve the engineering community. Please feel free to contact us with any comments or suggestions.

MatWeb's database is comprised primarily of data sheets and spec sheets supplied by manufacturers and distributors - let them know that you saw their material data on MatWeb.


The CAD portal is freely available to millions of CAD users worldwide, with hundreds of supplier catalogs and 100 million CAD models and product datasheets suitable for the design, purchasing, manufacturing or maintenance processes.


Free lecture notes, exams, and videos from MIT. No registration required.

MIT OpenCourseWare (OCW) is a web-based publication of virtually all MIT course content. OCW is open and available to the world and is a permanent MIT activity.

MIT OpenCourseWare is a free publication of MIT course materials that reflects almost all the undergraduate and graduate subjects taught at MIT.


As part of Google's mission to organize the world's information and make it universally accessible and useful, we're constantly working to expand the diversity of content we make available to our users. With Google Patents, you can now search the full text of the U.S. patent corpus and find patents that interest you.

All patents available through Google Patents come from the United States Patent and Trademark Office (USPTO). Patents issued in the United States are public domain documents, and images of the entire database of U.S. patents are readily available online via the USPTO website.

Google Patents covers the entire collection of issued patents and millions of patent application made available by the USPTO, from patents issued in the 1790s through the present. We don't currently include international patents, but we look forward to expanding our coverage in the future.