What is illiteracy?

Illiteracy refers to those who can't read or write. There used to be many illiterate people in our country, like grandma's generation or even earlier. It's less now. In the past, many people couldn't afford to read books, but now they attach importance to education. Coupled with nine-year compulsory education, many children will not be illiterate and don't know a word. My grandmother didn't know many words before, but she was very studious. When watching TV or singing, she always asks my brother and me some words that she doesn't know, but my hometown is not very good, because I left home for school in Mandarin, and many people can't speak my hometown dialect, so I often ask my mother for help in translation.