Simplify the following text for a Grade 8 native English-speaking person.
Original: The U.S. customary units have common roots with the imperial units , which were used in the British Empire . Many U.S. units are virtually identical to their imperial counterparts , but the U.S. customary system developed from English units in use before the imperial system was standardized in 1824 , and there are several numerical differences from the imperial system .
Simplified: It is similar to the British Imperial units .