What are real constants in java?

Java

"real" numbers, in any programming language, are actually approximations of what is called a "real number" in math. Basically, a number that can handle decimals - but unlike the actual real numbers, of limited precision.

In Java, the "real" data types are float, and double. double has greater precision.

A "constant" in Java is similar to a variable, but its value can't be changed after it has been assigned a value.