what is an acre?
An acre is a two dimensional unit of measurement, typically used to measure land. It’s size is about equivalent to 90 yards of football field.
What many people don’t realize is that the acre is not a universal measurement – the United States uses the survey acre while most other countries in the world use the international acre. The measurements are not the same, but they are very similar, and so this does not typically cause major confusion.
An acre is 43,560 square feet, which is one foot by one foot. So the conversion of acres to square feet is pretty simple, you just multiply by 43,560, or to go from square feet to acres you divide by 43,560.
the history of the acre
The acre is a term that originated in the Middle Ages in England. It came from a word in the Old English meaning open field, and was used to describe the amount of land a single person and a single ox could plow in a single day. This was a very practical terms, as it allowed lords to allot land to families and communities, and know how much they could work efficiently.
The word meant different things in different European countries until it was standardized in the 1800s, again by the British. The United States, still angry about the War of 1812, refused to follow the standard, and instead ended up with what is now known as the survey acre.
When most of Europe switched over to the metric system, that pretty much removed the ambiguity of the different acres, but in some countries the international acre is still used. Thankfully, as acres of land are not transported from one country to another, and that the difference is very small, it doesn’t really cause too many problems.