Summary  
This chapter introduces how to define a struct as a custom composite data type in C and shows how to instantiate a struct variable with specific field values.  

General domain of usage  
Scientific computing

Using the visual cue at the end of first chapter , let's create a data type to describe a chemical element:

```
struct chemicalElement
{
	char name[3];
	int atomicNum;
	int valency;
	double mass;
};
```


>Note
>
>The mass and sequence number cannot be negative, so it would be more efficient to use the `unsigned short int` data type.


Now, we can “create” a chemical element:

The code will look like this:
```
#include "stdio.h"

struct chemicalElement
{
	char name[3];
	int atomicNumber;
	int valency;
	double mass;
};

int main()
{
	struct chemicalElement silicon = {"Si", 14, 4, 28.08};
	return 0;
}
```


Access to struct fields will be discussed in the next chapter.

Try to describe the geometric point `A` with a structure.

The course covers the principles of creating and using structures, their memory and methods of data manipulation.

In this section you will learn what a structure is, why they exist and how to create them.

In this section we will review what pointers are, learn why pointers are used in structures and, most importantly, how this connection is implemented.

In this section, you'll learn how structures are stored in memory, see what alignment and padding are, and get acquainted with unions.

In this section you will learn about the features of nested structures, their application within other structures, get acquainted with anonymous structures and their application, and also superficially familiarize yourself with the most common data structures.

In this section you will implement a simple but very common data structure Linked List, and also create the necessary functions for working with the list.

Creating Your First Struct

Solution

Awesome!

Creating Your First Struct

Solution