The document discusses different types of manometers used to measure pressure, including acrylic body single limb manometers, acrylic body inclined manometers, inclined tube manometers, single limb manometers, U-tube manometers, and U-type manometers. Each type of manometer works by using liquid columns at different heights within tubes to indicate pressure differences. The manometers are made of clear acrylic or glass tubes and provide accurate pressure measurements.