These are sometimes known as 'quote marks.'
Sometimes they come in pairs, like the ones in the picture.
Sometimes there is just one.
They go at the top of the line.
They are used to mark out something that someone actually said. They curve around and enclose the exact words that someone said.
Look at this sentence:
Mary told me that the school had burned down.
There are no speech marks, because it doesn't give the exact words that Mary said.
But if I tell you exactly what Mary said, then I give her words in speech-marks, like this -
Mary said to me, "The school has burned down!"
You might also use them in an essay if you are quoting someone.
'Quoting someone' means to give the exact words they said or wrote.
You can quote them to support your argument, or to give an example of their work.
You put quote marks around their exact words, so that no one can say you are stealing their work, and pretending that you wrote it yourself.
For instance, if I was writing an essay about Oliver Cromwell, I might write:
Cromwell was a godly man, and believed that God and his faith helped him to win battles. In talking about his New Model Army, he said, "I chose such men as had the Fear of God before them, and made some conscience of what they did: and from that day forth, I say unto you, we were never beaten."
The words that Cromwell actually wrote are inside the quote marks.
You can also use speech marks - or quote marks - to pick out a word, or letter, and draw attention to it.
So I might write:
The letter 'e' is the most used letter in English. There are nine in this sentence alone!
Or I might write:
The little word 'set' has more meanings than any other word in the English dictionary.
In the first sentence, I put quote marks around the 'e', to show that I am talking about the letter itself - I'm not using it to spell anything.
In the second sentence, I'm not using any of the meanings of the word 'set' - I am talking about the word itself. So I pick the word out with quote marks.
Often speech marks are used to show that the writer doesn't really mean the word that they're using.
Imagine if someone borrowed something from you, and then didn't return it for a year, even though you keep asking them for it,
Finally, they bring it back, and act as if they're doing you a big favour.
You might say, sarcastically, "Oh, you're so kind."
Imagine the tone of voice you would say that in. You don't really think they're kind, and you don't want them to think you're pleased.
Well, that's the tone of voice that quote-marks sometimes mean.
They're often used when the writer is a little embarrassed to be using those words - or doesn't mean them.
Writers sometimes use them when they can't be bothered to think of better words. The quote marks are there to say something like, 'I don't think this is the best word to use but I can't think/can't be bothered to think/don't know another.'
This is not a good way to use quote marks.
Either use the words you thought of without quote marks - or think of a better way of saying what you want to say.