A simple article on a not-so-simple subject.
So amazingly complicated.
I haven’t written many editing articles dealing with grammar because, well, there are many sites out there that do it much better. But I do want to briefly discuss “Who vs. That” because, as an editor, I see it done incorrectly so often, and it’s one of those grammar things that seems like it should have a simple hard-and-fast rule but . . . doesn’t. Not really, anyway. Like I said: complicated.
Here’s the basic guideline:
WHO refers to people.
THAT refers to groups and things. (And sometimes people.)
Jordan is who ate all the pie.
The company that sold beans went out of business.
As you can see, when following up a noun with a relative pronoun, if that noun is not a person, not a human being, you use “that.”
A good business is one that listens to its customers.
(Note also the use of “its” — companies are not alive, so don’t use “their.”)
The dog that stole the sandwich had peed on the sofa.
Most benches that in are parks don’t have quiches under them.
You only ever use “who” when referring to people.
Most people who walk this way don’t realize how silly they look.
She is an actress who was known for her entrepreneurship.
Where it gets tricky is that you can use “that” to refer to people too.
The man that sold me the hot dog disappeared.
The people that invested in the hot dog shop were disappointed.
This is quite common, and when editing, I have to decide whether to change these to “who” (or “whom,” as the case may be) or leave as is.
Frustratingly for some people, this “rule” works on a case-by-case basis. Sometimes it simply sounds better to have “that” follow a person noun, and sometimes you just want to avoid being dehumanizing (“the woman that gave me a gift”). The most important thing is that “who” is reserved for people and nothing else; don’t say, “the car who broke down.”
Matters can get further complicated with the addition of a compound subject with both objects and people (“the employees and the tools that were no longer working”), for possessive terms (“the printer whose cartridges were empty”), if animals should be included as part of “who” (personal preference, IMO), how to deal with words like “groups” and “team,” and where “which” and “this” and “whom” and “these” fit into everything.
But that’s a lesson for another time.
In short, “who” and “that” are interchangeable for people, and only use “that” in most other instances. Personally, I suggest using “who” as often as possible when referring to people and save “that” for everything else.