Window tax, otherwise known as the glass tax, was a tax levied on property owners during the 18th and 19th centuries based on the number of windows in their home or business. This tax was implemented to increase revenue for the government during wartime, but it became widely unpopular among those who were subject to it. As a result, many people came up with alternative names for this tax such as light tax, sash tax, and house tax. Regardless of the name, the window tax was eventually abolished in the 1850s as it was deemed an unfair burden on the lower classes.