I shop. You shop. We all shop and hope to get into that express lane.

You know the one I’m talking about. The ones with that “10 Items or Less” sign posted near the front – telling us, in grammatically incorrect fashion, how many items we’re allowed to have to live life in the fast lane.

Of course, we can all understand what these signs are saying, their error isn’t so outrageous that we get confused. But it shows how poor grammar can quickly become the norm when we don’t understand the difference.

So, why exactly is “10 items or less” wrong?

Less and fewer are used in similar ways, but there is a key difference in that “fewer” is used for things that are countable, while “less” is used for singular or uncountable things. An example is that a smaller pool would have fewer gallons of water, and less space to swim. Or that there are fewer feuds in the world, and less hate as a result.

Airlines want to fly more people on planes, so there is less leg-room.

There are fewer apples than oranges in the basket.

Dictionary.com says “less” and “fewer” have been used almost interchangeably since the time of King Alfred, who reigned from 871 to 899 (fun fact for the day). Whether or not continuing to misuse these words because they have been for over a thousand years makes it okay is a debate for another day.