Hello World

Let's write our first hello world program, we can start by initializing a module. For that, we can use the go mod command.

$ go mod init example

But wait...what's a module? Don't worry we will discuss that soon! But for now, assume that the module is basically a collection of Go packages.

Moving ahead, let's now create a main.go file and write a program that simply prints hello world.

package main

import "fmt"

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

If you're wondering, fmt is part of the Go standard library which is a set of core packages provided by the language.

Structure of a Go program

Now, let's quickly break down what we did here, or rather the structure of a Go program.

First, we defined a package such as main.

package main

Then, we have some imports.

import "fmt"

Last but not least, is our main function which acts as an entry point for our application, just like in other languages like C, Java, or C#.

func main() {
	...
}

Remember, the goal here is to keep a mental note, and later in the course, we'll learn about functions, imports, and other things in detail!

Finally, to run our code, we can simply use go run command.

$ go run main.go
Hello World!

Congratulations, you just wrote your first Go program!