The main difference between .class files and .exe files is the type of code they contain and the platform they can run on.
A .class file is a compiled Java bytecode file that can be executed on any platform that has a Java Virtual Machine (JVM) installed. It contains compiled code that can be interpreted by the JVM at runtime, and it is not specific to any particular operating system. When you compile a Java program, the resulting output is a .class file.
On the other hand, an .exe file is an executable file that contains compiled machine code that is specific to a particular operating system and hardware architecture. It can only be executed on the platform for which it was compiled. Typically, .exe files are used on Windows operating systems to distribute software applications.
In summary, the main difference between .class files and .exe files is that .class files contain Java bytecode that can be executed on any platform that has a JVM installed, while .exe files contain machine code that is specific to a particular operating system and hardware architecture.