Text types are a category of variables in programming that allow us to manipulate and work with text data, such as words, phrases, names, and messages.
These types of variables are very common in our programs (for example, a person’s name, a shipping address, or the text to be displayed to the user in a dialog window).
This is because humans use words and text to communicate. However, for a computer, handling text is not as straightforward and natural. Thus, we have had to build the necessary structures to manage them.
In general, we will frequently encounter two types of text variables in different programming languages:
- Char, for individual characters
- String, for complete strings of text
The char type
The char variable type (short for “character”) is the basic unit of text used in many programming languages. It represents a single character, such as a letter, a number, or a symbol.
In reality, a computer does not understand anything about characters or text. They can only handle numbers. So, how are characters stored in a computer?
This is where character encoding tables, such as ASCII or Unicode, come into play. These tables assign a unique number to each character (for example, the character “A” is represented by the number 65 in the ASCII table).
In this way, when we work with char variables in a program, we are actually manipulating the numbers that represent the characters according to a specific encoding.
The string type
While char is the basic unit of text, in most cases we need to work with longer text strings that contain multiple characters. This is where the string variable type comes into play.
A string is the “real text” variable type. Unlike char, which represents a single character, a String can contain a word, a phrase, or even a complete paragraph.
In many programming languages, a string is simply a collection of chars. For example, in C.
However, to simplify the handling and manipulation of text strings, programming languages generally provide more complex objects designed to work with texts (which are also built around a collection of chars).
Example of text types in different languages
In the languages derived from C, such as C++, C#, or Java, both types, char and string, exist. For example, this is how you would create a variable of each type in C#:
char myCharacter = 'A';
string myString = "Hello, world!";Note that in these languages, the value of a char is enclosed in ', while string values are enclosed in ".
This is identical to the case in C++, with the exception that string is defined in the std namespace.
char myCharacter = 'A';
std::string myString = "Hello, world!";In JavaScript, only the string type exists, and there is no specific char type. Additionally, for value usage, we can use ', ", or ` interchangeably.
let myCharacter = 'A';
let myString = "Hello, world!";Similarly, in Python, only the string type exists. To indicate values, we can use ' or " interchangeably.
myCharacter = 'A'
myString = "Hello, world!"