Update README with an example

README.md

diff --git a/README.md b/README.md
index 185aa0b..1217a52 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # mapstructure
 
-mapstructure is a Go library for converting generic map values to structures
+mapstructure is a Go library for decoding generic map values to structures
 and vice versa, while providing helpful error handling.
 
 This library is most useful when decoding values from some data stream (JSON,
@@ -8,3 +8,33 @@
 until you read a part of it. You can therefore read a `map[string]interface{}`
 and use this library to decode it into the proper underlying native Go
 structure.
+
+## Example
+
+```go
+import "mapstructure"
+
+type Person struct {
+	name   string
+	age    uint
+	emails []string
+}
+
+// You can imagine that the "input" comes from some external source
+// such as decoding JSON or something.
+input := map[string]interface{}{
+	"name": "Mitchell",
+	"age": 91,
+	"emails": []string{"foo@bar.com", "bar@baz.com"},
+}
+
+var result Person
+err := mapstructure.Decode(input, &result)
+if err != nil {
+	panic(err)
+}
+
+// The value of "result" now contains what you would expect. The decoding
+// process is properly type-checked and human-friendly errors are returned,
+// if any.
+```