C vs C++ – What‘s The Difference?

The C and C++ programming languages are two of the most important and influential languages in the history of computing. Nearly every other modern language has been influenced by or implemented in C or C++, including Java, Python, JavaScript, and more.

While C++ is an extension of C and the two languages have a lot in common, there are also some significant differences in their features and typical uses. In this article, we‘ll explore the origins of C and C++, their similarities and differences, and some tips on how to get started learning them.

The Origins of C

The C programming language was developed in the early 1970s at Bell Labs by Dennis Ritchie. It was based on an earlier language called B, which Ritchie had helped create a few years prior.

C was designed as a systems programming language. Its primary purpose was to implement operating systems and other software that interacts closely with computer hardware. In fact, one of the first major projects written in C was the Unix operating system, which Ritchie and others at Bell Labs started re-implementing in C in 1972.

C provided a number of advantages for systems programming compared to assembly languages and earlier high-level languages:

• It provided low-level access to memory
• It required minimal run-time support
• It was portable across different machines
• It was fast and efficient
• It had a concise syntax

These features quickly made C a popular choice for systems programming and other performance-critical code. Even today, key software like operating systems, device drivers, and embedded systems are often written in C.

The Origins of C++

In 1979, a computer scientist named Bjarne Stroustrup began developing an extension to the C language, initially called "C with Classes". His goal was to add support for object-oriented programming to C, inspired by the Simula language.

Compared to procedural languages like C, object-oriented languages allow data and functions to be bundled together into objects. Objects can inherit attributes from other objects. This provides better code organization and reuse for large projects.

In 1983, Stroustrup‘s language was renamed to C++. Over the following years, he and others continued extending the language with features like operator overloading, virtual functions, multiple inheritance, templates, and exception handling.

These features made C++ a substantially more complex and powerful language than C, well-suited for large applications with hundreds of thousands or millions of lines of code. The object-oriented features were especially influential, and inspired later object-oriented languages like Java and C#.

Key Similarities between C and C++

Since C++ was derived from C, the two languages have a lot in common, including:

• Similar syntax for variables, expressions, functions, control structures, etc.
• Many of the same keywords and operators
• Compiled into machine code, with minimal runtime overhead
• Provide low-level access to system memory and resources
• Source files conventionally have .c and .cpp extensions

In fact, most C code can be compiled as C++ with few or no changes. C++ maintains nearly full backwards compatibility with C.

Key Differences between C and C++

At the same time, C++ adds a large number of features on top of C, so the two are far from interchangeable. Some of the most notable differences are:

• C++ supports object-oriented programming with classes, inheritance, virtual functions, etc.
• C++ supports generic programming with templates
• C++ allows operator overloading and function overloading
• C++ has exception handling with try/catch blocks
• C++ includes a much larger standard library, with support for strings, containers, algorithms, and more
• C++ allows declarations almost anywhere in a function, not just at the top

There are also a number of more subtle differences in the syntax and semantics of certain features the two languages share, like the behavior of structs.

So while C++ is largely a superset of C, and most C code can be used in a C++ program, the reverse is not true. Most non-trivial C++ programs will not compile as C.

Major Uses of C

As mentioned earlier, C is mainly used for systems programming and other applications that require close interaction with hardware. Some of its most common applications include:

• Operating systems kernels and drivers
• Embedded systems like IoT devices and real-time controllers
• Language runtimes and virtual machines
• High-performance computing and scientific simulations
• Legacy applications in fields like aerospace and telecommunications

That said, while C remains popular for these use cases, it has been largely displaced by newer languages for application programming. It‘s syntax and lack of modern features can make it difficult to write and maintain larger codebases in pure C.

Major Uses of C++

In contrast, in addition to system-level software, C++ is used for a wide variety of applications, including:

• Video games and game engines like Unreal Engine
• Web browsers like Chrome and Firefox
• Productivity software like Microsoft Office and Adobe Photoshop
• Database servers like MySQL and MongoDB
• Financial and banking systems
• Medical software like radiation therapy planning systems

C++‘s combination of performance and high-level object-oriented features make it well-suited for these large, complex, performance-sensitive applications. It remains one of the most widely-used languages in many of these domains.

Learning C and C++

If you‘re interested in learning C or C++, where should you start? Here are a few tips:

• If you‘re new to programming, C may be easier to learn first, as it is a smaller, simpler language. Once you‘ve learned C, it‘s easy to pick up C++.

• If you already know another object-oriented language like Java or C#, learning C++ first may be the better choice, as many of the concepts will already be familiar.

• There are a wealth of good introductory books and courses for both languages. For C, the classic "The C Programming Language" by Kernighan and Ritchie is still an excellent resource. For C++, Stroustrup‘s "The C++ Programming Language" and Meyers‘ "Effective C++" series are highly regarded.

• Both languages have a reputation for being complex and allowing dangerous code. It‘s important to learn common pitfalls and best practices to write safe, correct programs.

• C++ is a very large language and it‘s not necessary to learn every feature to use it effectively. Focus on core concepts first.

With dedication and practice, proficiency in C and C++ will serve you well in a wide variety of domains and open up opportunities to work on many interesting systems and applications.

Conclusion

C and C++ are two of the most important programming languages ever created, and remain widely used today across many application domains. While they share similar syntax and many features, C++ adds support for object-oriented and generic programming that makes it a vastly more complex and powerful language.

Picking between the two largely depends on the type of software you want to develop. For low-level systems programming, C is often the better choice. For large applications, C++ is usually the way to go.

In either case, learning these foundational languages will deepen your understanding of how computers and programming languages work, and serve you well in a career in software development.