diff --git a/defer/main.go b/playground/defer/main.go
similarity index 100%
rename from defer/main.go
rename to playground/defer/main.go
diff --git a/for-range-semantics/main.go b/playground/for-range/main.go
similarity index 100%
rename from for-range-semantics/main.go
rename to playground/for-range/main.go
diff --git a/interface-semantics/main.go b/playground/interface-semantics/main.go
similarity index 100%
rename from interface-semantics/main.go
rename to playground/interface-semantics/main.go
diff --git a/the_go_programming_language/ch04/slice.go b/playground/slice/slice.go
similarity index 100%
rename from the_go_programming_language/ch04/slice.go
rename to playground/slice/slice.go