Explain the use of Go's JSON encoding and decoding for data serialization?

In Go, the encoding/json package provides support for encoding Go data structures into JSON format and decoding JSON data into Go data structures. JSON is a widely used format for data serialization and exchange, and is supported by many programming languages and web APIs.

Here is an example of encoding a Go data structure into JSON:

import (
    "encoding/json"
    "fmt"
)

type Person struct {
    Name string `json:"name"`
    Age  int    `json:"age"`
}

func main() {
    p := Person{Name: "John Doe", Age: 42}
    b, err := json.Marshal(p)
    if err != nil {
        fmt.Println("Error:", err)
    }
    fmt.Println(string(b)) // prints {"name":"John Doe","age":42}
}

In this example, we define a Go data structure called **Person** with two fields: **Name** and **Age**. We use struct tags to specify the corresponding JSON field names for each field. Then we create an instance of the **Person** struct, and use the **json.Marshal()** function to encode it into a JSON byte slice.

Here is an example of decoding a JSON byte slice into a Go data structure:

import (
    "encoding/json"
    "fmt"
)

type Person struct {
    Name string `json:"name"`
    Age  int    `json:"age"`
}

func main() {
    b := []byte(`{"name":"John Doe","age":42}`)
    var p Person
    err := json.Unmarshal(b, &p)
    if err != nil {
        fmt.Println("Error:", err)
    }
    fmt.Printf("%#v\n", p) // prints main.Person{Name:"John Doe", Age:42}
}

In this example, we define the same **Person** struct as before, and create a JSON byte slice representing a **Person** object. Then we use the **json.Unmarshal()** function to decode the JSON byte slice into a **Person** struct.

The **encoding/json** package supports many other features for customizing JSON encoding and decoding, such as handling embedded structs, ignoring empty fields, and customizing field names and types.