Cubic Centimeter (cm³ or cc)
A cubic centimeter (cm³/cc) is a metric volume unit equivalent to one milliliter. Established with the metric system in the 1700s, it is frequently employed in scientific, engineering, and medical settings to measure small quantities accurately. The abbreviation “cc” is particularly prevalent in medical prescriptions for liquids and in the automotive field for specifying engine size. Since it matches the volume of a milliliter, the cubic centimeter is easily compatible with the rest of the metric system while remaining important in specialized applications.
Imperial Gallon (imp gal)
The imperial gallon, shown as imp gal, is a British unit equal to 4.54609 liters. It came from English wine and drink measures in the 1800s and became official in 1824. The imperial gallon was used throughout the British Empire and is still used in the UK and some other countries for fuel and beverages. The liter is now used almost everywhere, but the imperial gallon still exists because of custom and local use.