About Temperature is a tutorial that covers several topics about temperature, thermometers and thermodynamics. The text clearly explains topics such as the development of thermometers and temperature scales, heat and thermodynamics, kinetic theory, thermal radiation and the temperature of the universe. There are diagrams and helpful links. A version of the web page is available in Spanish as well. This website would be useful for students or teachers researching thermometers or introductory thermodynamics.