Golang provides built-in support for base64 encoding/decoding in the package `encoding/base64`. 

# Syntax

Commonly used methods for encoding and decoding:
1. Encoding:  
```go
func (enc *Encoding) EncodeToString(src []byte) string
```

**`EncodeToString`** takes a byte #key# slice: a dynamically-sized, flexible abstraction of array  #key# and returns a base64 encoding as a string.

2. Decoding: 
```go
func (enc *Encoding) DecodeString(s string) ([]byte, error)
```  

**`DecodeString`** takes a base64 encoded string and returns the decoded data as a byte slice. It will also return an error in case the input string has invalid base64 data.

The types of encoding available are:
- **`StdEncoding`**: standard base64 encoding
- **`URLEncoding`**: alternate base64 encoding used in URLs and file names
- **`RawStdEncoding`**: standard, raw, unpadded base64 encoding
- **`RawURLEncoding`**: unpadded alternate base64 encoding for URLs and file names

# Example

Here is an example of encoding and then decoding the string, "Hello World!" using base64 encoding with `StdEncoding`.

package main

import (
    "encoding/base64"
    "fmt"
)

func main() {

    // String to encode
    str := "Hello World!"

    // base64.StdEncoding: Standard encoding with padding
    // It requires a byte slice so we cast the string to []byte
    encodedStr := base64.StdEncoding.EncodeToString([]byte(str))
    fmt.Println("Encoded:", encodedStr)

    // Decoding may return an error, in case the input is not well formed
    decodedStr, err := base64.StdEncoding.DecodeString(encodedStr)
    if err != nil {
        panic("malformed input")
    }
    fmt.Println("Decoded:", string(decodedStr))
}

> For more information on the methods available as part of the `encoding/base64` package, check out the [official docs](https://golang.org/pkg/encoding/base64/).

Golang base64 encoding/decoding

Golang provides built-in support for base64 encoding/decoding in the package encoding/base64. 