The Wolfram|Alpha website is an ambitious, long-term project to make all systematic knowledge immediately computable by anyone. Enter your question or calculation and Wolfram|Alpha uses its built-in algorithms and a growing collection of data to compute the answer. It aims to collect and curate all objective data; implement every known model, method, and algorithm; and make it possible to compute whatever can be computed about anything. The goal is to build on the achievements of science and other systematisations of knowledge to provide a single source that can be relied on by everyone for definitive answers to factual queries. To see what the site is capable of look at the Examples where you will be able to choose by subject area or there is a quick video overview. You can search by chemical formula, for example, and you will given chemical names and formula as well as basic, liquid and thermodynamic properties; chemical identifiers such as CAS registry number are also given. On a more trivial note, it can also help when playing scrabble!

There is also a Wolfram|Alpha for Educators for classroom use.