recently i've made a java program consisting of 4 classes, is there any way I can make this into a file that will run on other machines, something like a C++ .exe file? I've heard about JAR files, but not really too sure what they are. Can anyone help, I really want to have some way of installing/running my program on other machines?
Make sure a JRE (Java Runtime Environment) of the right version is installed on the other machine and then you can run your Java program without trouble.
You can't drive a car that doesn't have an engine installed, so to run a Java program, you must have Java installed on the computer.
If you're not sure that your users will have Java installed, you could create a setup program for your Java program with for example IzPack. It can automatically download and install Java on a computer if necessary while installing your program.