Type variable

A type variable is like a special box that can hold different types of things inside. Imagine you have a toy box and sometimes you put in a toy truck or a doll or a puzzle. The toy box is the type variable and the different toys are the different types that can be put inside it. Type variables are like a toy box that programmers use to hold different types of data. They make programming more flexible because you can use the same code with different types of data. So, just like your toy box can hold different toys, a type variable can hold different types of data.