diff --git a/FAQ.md b/FAQ.md
index 33ce7ca..0302d14 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -14,6 +14,8 @@ As of Go 1.10, build cache system is changed and you might not need the above ti
 
 With the build tag, `go get -u github.com/hajimehoshi/ebiten/...` doesn't install the example binaries in your `$GOPATH/bin`.
 
+Such build tags are an idiom you can find e.g. in `golang.org/x/image/example/font/main.go`.
+
 # Graphics
 
 ## How to draw lines?