Understanding The Difference Between C And C++

Updated 16 November 2023

C and C++ are two of the most prominent programming languages in use today. If you want to get a job as a computer programmer, you are required to have a basic understanding of how these two languages work. Judging by their names, you may think that C and C++ are very similar, which is true to an extent, but there are some key differences as well.

In this article, we cover some key difference between C and C++ and see why knowing these differences is important.

Importance Of Knowing The Difference Between C And C++

Here are a few reasons that make knowing the difference between C and C++ important for you:

Helps in understanding the different coding applications

C++ is an extension of C and hence there are a lot of similarities between the two. At the same time, there are several differences as well that become very important while selecting which of these two to use for coding an application or a feature in an application. So, knowing the differences between C and C++ can help you understand which one is better applicable for a particular use case.

Helps in making an informed career choice

It is important to understand the difference between C and C++ because it enables you to make an informed career choice. Once you understand the difference, you can decide which language you require to learn. If you are already working in one of these languages, you can choose to learn the other one too if you feel that it can contribute to your career growth. If your job involves coding or managing projects in both languages, understanding the difference can help you decide which language to use in a given project.

Can be an important topic for interview questions

Knowing the differences between C and C++ can be helpful when you are interviewing for a role that uses C or C++. Since these two programming languages are very extensively used in the market, there are high chances that you might be asked questions about these when you are interviewing for the role of a programmer.

The interviewer may ask you questions about one of the languages or about concepts that are common to both or derive from both. To be able to answer such questions well, you are required to have a thorough understanding of the differences between the two programming languages.

What Is C?

C is a very popular programming language. This popularity is because of how simple it is to learn C. Because of this, many aspiring programmers study C in their initial days of learning to code, as it helps them in learning other programming languages in the later stages of their careers.

Today, C is used in a variety of applications. For example, you can find it in:

The development of operating systems
The development of internet browsers
Desktop applications
System applications
Internet-of-Things applications

What Is C++?

C++ is an extension of the C language. It is a cross-platform programming language that gives good control over system resources. Programmers usually use it for developing a system of applications, such as an operating system or a browser. It is an ideal choice for coding for multi-platform systems. But, it has a complex syntax and a wide range of features, which can often be overwhelming for new programmers. Another drawback is that it does not support checking runtime errors, meaning that you cannot detect errors while running the software.

Now, C++ can be found in many places, including:

Internet browsers
Video games
Cloud systems
Operating systems
Database software

Differences Between C And C++

C and C++ have many similarities because C++ is an extension of C. But, there are still many differences. Here are the major differences between C and C++:

Programming type

The first major difference between C and C++ is that C is a procedural-oriented language, while C++ is an object-oriented language. Object-oriented means that when you create an object in C++, the object contains both data and functions. But, in a procedural language, you are required to write functions separately to perform operations on the data.

Application development

When it comes to developing server-side applications, games or network applications, C++ is the preferred programming language. C language, on the other hand, is better suited for low-level implementations and embedded systems.

Ease of use

C++ is typically an easier language to use, as it uses object-oriented code. With C, the programmer is required to tell the program to do everything. In addition, there are more possibilities with C, which can make it overwhelming to use.

Compatibility

C++ is compatible with other generic programming languages, while C is not. C++ is also compatible with C programs.

Level of abstraction

The C programming language is much less abstract. It focuses on the specific steps required to solve a problem. But C++ focuses on the objects and not necessarily the steps, giving it a higher abstraction level.

File extension

The two programming languages use different file extensions when creating a file. C uses a “.c” extension while C++ uses the “.cpp” extension.

Support of inline function

An inline function is when the compiler places a copy of a function's code at each point where the function is called. Using this function can significantly reduce overhead. C does not support this feature, while C++ does.

Security

Data within the C language is not secured, while it is in C++. This means external functions cannot access the data in C++.

Number of keywords

Keywords are pre-defined words that are reserved in a programming language. C contains 32 different keywords, while C++ contains 52.

Variable declaration

With C, you are required to declare your variables at the very beginning of the program. With C++, you can declare your variables at any time. In addition, C allows for multiple declarations of global variables, while C++ does not.

Ease of mapping

Maps store elements that are related to one another. The mapping between data and functions in C is very complicated, whereas it is much simpler to do in C++, using Classes and Objects.

Inheritance

Inheritance is basing an object or class upon another object or class. This is used in object-oriented programming, meaning it is supported in C++ but not in C.

Standard input and output

The standard commands for input and output in C are scan and print. To do this in C++, you are required to use cin and cout.

Support for pointers and references

Pointers are variables that “point” to the address of another variable. Using these allows you to allocate memory dynamically at runtime. A reference variable is an alias or another name for an already existing variable. A reference can be used to refer to a variable. C supports only the use of pointers, while C++ supports both pointers and references.

Programming approach

C uses a top-down programming approach, while C++ uses a bottom-up programming approach. In top-down, you first create an overview of the problem, then refine it into smaller parts. With bottom-up, you specify the individual parts, which are then linked to create a complete system.

Function overloading

Function overloading is when you create multiple functions of the same name but different implementations. Function overloading is not allowed in C but is allowed in C++.

Exception handling

Exception handling is used to help you identify runtime errors. Exception handling is not available in C; but there are some ways to work around this. Exception handling is native in C++.

Data types

The string and Boolean data types are only available in C++. C only uses built-in and primitive data types.

Focus

The focus of both of these languages is different. C focuses on the process, while C++ focuses on the data.

Header file

The header file used by C is stdio.h, while the header file used by C++ is iostream.h.

Information hiding

In C++, data is hidden by encapsulation to ensure that everything is used as intended. This function is not available in C.

Memory allocation functions

While both languages allow for memory allocation, they do so differently. C uses the malloc() and calloc() functions to allocate memory, while C++ has a new operator for this. They also de-allocate memory differently.