GolangでHello World! ref: http://qiita.com/fk_2000/items/d691c9e1ffff170359db

file0.go

package main

import "fmt"

func main() {
    fmt.Println("Hello World!")
}

file1.txt

$ ls -ltr
total 3160
-rw-r--r--  1 val  staff       76 Oct  7 10:47 hello.go
-rwxr-xr-x  1 val  staff  1607616 Oct  7 10:47 hello

file2.txt

$ ./hello
Hello World!

file3.txt

$ go run hello.go
Hello World!

file4.go

package main

import (
  "fmt"
  "time"
)

func main() {
    fmt.Println("The current time is", time.Now())
}

file5.txt

$ go run time.go
The current time is 2016-10-07 11:00:11.027383849 +0900 JST

file6.txt

$ date
Fri Oct  7 11:00:19 JST 2016