The document compares the syntax and features of C, Java, and Go programming languages. It discusses their file extensions, compilers, variable declaration, data types, operators, control flow statements, functions, arrays, maps, structs, classes, interfaces, pointers, error handling and concurrency models. The key differences summarized are that C uses .c extension and header files while Java uses .java extension and bytecode. Go can compile and run code directly without a virtual machine. Both Java and Go support OOPs concepts like classes while C uses structs. Go supports concurrency using goroutines and channels.