So basically, sometimes people use computers to help them learn languages. You know how sometimes you play games on the computer? Well, sometimes people make games that help you learn new words in a different language. Or they make computer programs that help you with grammar or pronunciation.
It's kind of like having a special teacher that lives inside the computer and you can talk to it and it helps you learn things. Sometimes you might see a picture of something on the computer and you have to type in the word for it in a different language. Or maybe you listen to someone speak and then you have to say it back to them. All of these things can help you get better at speaking and understanding different languages. Pretty cool, right?