C was invented in the 1970s, while C++ and Java were invented in 1979 and 1991 respectively. C# was developed by Microsoft for the .NET framework and is closely related to Java. Bytecode is a highly optimized set of instructions for the Java virtual machine that allows Java programs to run on different platforms. The Java virtual machine interprets bytecode, improving security and portability while the just-in-time compiler included in Java 2 further improves performance by compiling bytecode to executable code on demand.