# 14. Strings

### String Types

String Types are used to store text like data.A string is an immutable sequence of bytes.

Go uses UTF-8 encoding to store strings.

> A character in UTF8 can be from 1 to 4 bytes long. UTF-8 can represent any character in the Unicode standard. UTF-8 is backwards compatible with ASCII. UTF-8 is the preferred encoding for e-mail and web pages - W3Schools.com

### Declaring String

Strings are declared using one of the following ways:

{% code title="main.go" %}

```go
	var str1 string = "Hello, World!"
	var str2 = "Hello, World!"
	str3 := "Hello, World!"
```

{% endcode %}

Zero value for string is empty string `""`

### Length of string

Build in `len` function can  be used to get number of bytes in string

{% code title="main.go" %}

```go
fmt.Printf("length of str1 is %d \n", len(str1))
```

{% endcode %}

### Sub-string operation

We can easily create substring from existing string using `s[i,j].`This operation always generates new string since string are immutable. `i` indicates starting index for substring including `i` and `j` indicates end index excluding `j`

{% code title="main.go" %}

```go
str4 := str1[7:13]

fmt.Println(str4)
```

{% endcode %}

### Blog Posts

{% embed url="<https://blog.golang.org/strings>" %}


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