Byte Slices

What are byte slices?

A byte slice is a slice of the byte data type ([]byte). Go knows that most byte slices are used to store strings and so it makes it easy to switch between this type and the string type. There is nothing special in the way we can access a byte slice compared to the other types of slices. What is special is that Go uses byte slices for performing file I/O operations because they allow us to determine with precision the amount of data we want to read or write to a file. This happens because bytes are a universal unit among computer systems.

Note: Because Go does not have a char data type, it uses byte and rune for storing character values. A single byte can only store a single ASCII character, whereas a rune can store Unicode characters. However, a rune can occupy multiple bytes.

Coding example

The small byteSlices.go program that follows illustrates how we can convert a byte slice into a string and vice versa, which we need for most file I/O operations.