Difference between C/C++

The C language was developed in 1972 by Dennis Richie at Bell Telephone laboratories, primarily as a systems programming language. That is, a language to write operating systems with. Richie’s primary goals were to produce a minimalistic language that was easy to compile, allowed efficient access to memory, produced efficient code, and did not need extensive run-time support. Despite being a fairly low-level high-level language, it was designed to encourage machine and platform independent programming.

C ended up being so efficient and flexible that in 1973, Ritchie and Ken Thompson rewrote most of the UNIX operating system using C. Many previous operating systems had been written in assembly. Unlike assembly, which ties a program to a specific CPU, C’s excellent portability allowed UNIX to be recompiled on many different types of computers, speeding it’s adoption. C and Unix had their fortunes tied together, and C’s popularity was in part tied to the success of UNIX as an operating system.

In 1978, Brian Kernighan and Dennis Ritchie published a book called “The C Programming Language”. This book, which was commonly known as K&R (after the author’s last names), provided an informal specification for the language and became a de facto standard. When maximum portability was needed, programmers would stick to the recommendations in K&R, because most compilers at the time were implemented to K&R standards.

In 1983, the American National Standards Institute (ANSI) formed a committee to establish a formal standard for C. In 1989 (committees take forever to do anything), they finished, and released the C89 standard, more commonly known as ANSI C. In 1990 the International Organization for Standardization adopted ANSI C (with a few minor modifications). This version of C became known as C90. Compilers eventually became ANSI C/C90 compliant, and programs desiring maximum portability were coded to this standard.

In 1999, the ANSI committee released a new version of C called C99. It adopted many features which had already made their way into compilers as extensions, or had been implemented in C++.

C++ (pronounced see plus plus) was developed by Bjarne Stroustrup at Bell Labs as an extension to C, starting in 1979. C++ was ratified in 1998 by the ISO committee, and again in 2003. A new version of the standard, known as C++0x (implying it will come out before 2010) is being developed as this is written.

The underlying design philosophy of C and C++ can be summed up as “trust the programmer” — which is both wonderful, because the compiler will not stand in your way if you try to do something unorthodox that makes sense, but also dangerous, because the compiler will not stand in your way if you try to do something that could produce unexpected results. That is one of the primary reasons why knowing how NOT to code C/C++ is important — because there are quite a few pitfalls that new programmers are likely to fall into if caught unaware.

C++ adds many new features to the C language, and is perhaps best thought of as a superset of C, though this is not strictly true as C99 introduced a few features that do not exist in C++. C++’s claim to fame results primarily from the fact that it is an object-oriented language. As for what an object is and how it differs from traditional programming methods, well, we’ll cover that in just a few sections.