Distinguishing C from C++

Plain C is a simple, low-level language, and it's nearly a subset of C++, which was originally named "C with classes". If you look at the size of the author's book on each language, you can immediately see the big complexity difference!

C textbook Kernigan and Ritchie, a thin paperback, versus Straustrup's Ocean Book on C++, a thick hardback.

Generally, these features are shared between C and C++:

Variables like "int" and "char"
Arithmetic operations like + - * /
Assignments like =, or += and such.
Functions, curly braces {}
if statements, switch statements
for loops, while loops, do loops
arrays
pointers

These features are only C++, not available in plain C:

Object oriented features like class and virtual methods. Plain C uses functions or structs for similar operations.
new and delete. Plain C uses functions named malloc and free instead.
templates. Plain C uses macros for similar features.
std::string. Plain C uses arrays of characters for strings, which are more error-prone.
std::cout and std::cin. Plain C uses printf and scanf, which I actually prefer, but are harder to learn, and can't be extended.
std::vector. Plain C uses bare arrays, and a function named realloc.
std:: anything else!

In this class, we'll be covering both the implementation of C++ features in plain C and assembly, and plain C as a language on its own. Quite a few large projects are built in plain C, including the linux kernel, and many system libraries.

CS 301 Lecture Note, 2014, Dr. Orion Lawlor, UAF Computer Science Department.