One inch is a unit of length in the British Imperial and United States customary systems. It is exactly equal to 2.54 centimeters or 25.4 millimeters in the metric system

. To visualize, one inch is about the width of a standard USB flash drive, the diameter of a typical bottle cap, the thickness of a hockey puck, or the length of a standard paperclip

. It is also 1/12 of a foot or 1/36 of a yard

. In summary:

• 1 inch = 2.54 cm = 25.4 mm
• 1 inch = 1/12 foot
• 1 inch = 1/36 yard
• Common objects about 1 inch long: USB flash drive width, bottle cap diameter, hockey puck thickness, paperclip length

This makes the inch a convenient and widely used unit for everyday measurements.