Pyrex is a brand name for glassware, introduced by Corning Incorporated in 1915. Originally, Pyrex was made from thermal shock resistant borosilicate glass. In 1998, Corning sold its consumer products division which subsequently adopted the name World Kitchen. Pyrex kitchen glassware manufactured and licensed for sale in the United States is now made of tempered soda-lime glass at the World Kitchen facility in Charleroi, Pennsylvania.

Pyrex products for the European Union continue to be made of borosilicate glass in France.

Pyrex laboratory glassware is also still made of borosilicate glass.

According to Carroll Gantz, Dr. Jesse Littleton of Corning discovered the cooking potential of borosilicate glass by presenting his wife with a makeshift casserole dish made from a cut down Nonex (a low expansion glass developed in 1908 by Dr. Eugene Sullivan) battery jar.

Corning went on to remove lead from the formula, and Pyrex was born.