lean into examples

examples/hello-world/hello-world.go

@@ -0,0 +1,9 @@
+// Our first program will print the classic "Hello world"`
+// message. Here's the full source code.
+package main
+
+import "fmt"
+
+func main() {
+    fmt.Println("Hello world")
+}

examples/hello-world/hello-world.sh

@@ -0,0 +1,17 @@
+# To run the program, put the code in `hello-world.go` and
+# use `go run`.
+$ go run hello-world.go
+Hello world
+
+# Sometimes we'll want to build our programs into
+# binaries. We can do this using `go build`.
+$ go build hello-world.go
+$ ls
+hello-world	hello-world.go
+
+# We can then execute the built binaries directly.
+$ ./hello-world
+Hello world
+
+# Now that we can run and build basic Go programs, let's
+# learn more about the language.