Pressed glass is process that got developed in United States during 1820s. It became popular in United States and companies started producing it after the invention of glass pressing machines. During the mid-19th century this became the most popular and inexpensive technique for producing glassware in large numbers. Production of presses glass was observed in manufacturing table sets and later it evolved to the production of pieces like lamps and candlesticks. Pieces of pressed glasses were made to join together with hot glass to make complicated pieces of glass out of this. Carnival glass is one such type and painted pressed glasses were made during 20th century.