diff --git a/lib/edoc/src/edoc_layout.erl b/lib/edoc/src/edoc_layout.erl
index 87018af25a36..c9761dc2a653 100644
--- a/lib/edoc/src/edoc_layout.erl
+++ b/lib/edoc/src/edoc_layout.erl
@@ -898,7 +898,7 @@ t_map(Es) ->
     ["#{"] ++ seq(fun t_utype_elem/1, Es, ["}"]).
 
 t_map_field([K,V]) ->
-    [t_utype_elem(K) ++ " => " ++ t_utype_elem(V)].
+    t_utype_elem(K) ++ [" => "] ++ t_utype_elem(V).
 
 t_record(E, Es) ->
     Name = ["#"] ++ t_type(get_elem(atom, Es)),
@@ -1095,6 +1095,10 @@ ot_type([#xmlElement{name = nonempty_list, content = Es}]) ->
     ot_nonempty_list(Es);
 ot_type([#xmlElement{name = tuple, content = Es}]) ->
     ot_tuple(Es);
+ot_type([#xmlElement{name = map, content = Es}]) ->
+    ot_map(Es);
+ot_type([#xmlElement{name = map_field, content = Es}]) ->
+    ot_map_field(Es);
 ot_type([#xmlElement{name = 'fun', content = Es}]) ->
     ot_fun(Es);
 ot_type([#xmlElement{name = record, content = Es}]) ->
@@ -1151,6 +1155,12 @@ ot_nonempty_list(Es) ->
 ot_tuple(Es) ->
     {type,0,tuple,[ot_utype_elem(E) || E <- Es]}.
 
+ot_map(Es) ->
+    {type,0,map,[ot_utype_elem(E) || E <- Es]}.
+
+ot_map_field(Es) ->
+    {type,0,map_field_assoc,[ot_utype_elem(E) || E <- Es]}.
+
 ot_fun(Es) ->
     Range = ot_utype(get_elem(type, Es)),
     Args = [ot_utype_elem(A) || A <- get_content(argtypes, Es)],
diff --git a/lib/edoc/test/edoc_SUITE_data/map_module.erl b/lib/edoc/test/edoc_SUITE_data/map_module.erl
index 94ee7e6f26f4..f242721637f0 100644
--- a/lib/edoc/test/edoc_SUITE_data/map_module.erl
+++ b/lib/edoc/test/edoc_SUITE_data/map_module.erl
@@ -1,6 +1,6 @@
 -module(map_module).
 
--export([foo1/1,foo2/3]).
+-export([foo1/1,foo2/3,start_child/2]).
 
 %% @type wazzup() = integer()
 %% @type some_type() = map()
@@ -25,3 +25,43 @@ foo1(#{ a:= 1, b := V}) -> V.
     Map :: #{ get => 'value', 'value' => binary()}) -> binary().
 
 foo2(Type1, {a,#{ "a" := _}}, #{get := value, value := B}) when is_map(Type1) -> B.
+
+%% from supervisor 18.0
+
+-type child()    :: 'undefined' | pid().
+-type child_id() :: term().
+-type mfargs()   :: {M :: module(), F :: atom(), A :: [term()] | undefined}.
+-type modules()  :: [module()] | 'dynamic'.
+-type restart()  :: 'permanent' | 'transient' | 'temporary'.
+-type shutdown() :: 'brutal_kill' | timeout().
+-type worker()   :: 'worker' | 'supervisor'.
+-type sup_ref()  :: (Name :: atom())
+                  | {Name :: atom(), Node :: node()}
+                  | {'global', Name :: atom()}
+                  | {'via', Module :: module(), Name :: any()}
+                  | pid().
+-type child_spec() :: #{name => child_id(),     % mandatory
+			start => mfargs(),      % mandatory
+			restart => restart(),   % optional
+			shutdown => shutdown(), % optional
+			type => worker(),       % optional
+			modules => modules()}   % optional
+                    | {Id :: child_id(),
+                       StartFunc :: mfargs(),
+                       Restart :: restart(),
+                       Shutdown :: shutdown(),
+                       Type :: worker(),
+                       Modules :: modules()}.
+
+-type startchild_err() :: 'already_present'
+			| {'already_started', Child :: child()} | term().
+-type startchild_ret() :: {'ok', Child :: child()}
+                        | {'ok', Child :: child(), Info :: term()}
+			| {'error', startchild_err()}.
+
+
+-spec start_child(SupRef, ChildSpec) -> startchild_ret() when
+      SupRef :: sup_ref(),
+      ChildSpec :: child_spec() | (List :: [term()]).
+start_child(Supervisor, ChildSpec) ->
+    {Supervisor,ChildSpec}.
diff --git a/lib/erl_docgen/src/docgen_otp_specs.erl b/lib/erl_docgen/src/docgen_otp_specs.erl
index 886194598f35..cbdbbbee8066 100644
--- a/lib/erl_docgen/src/docgen_otp_specs.erl
+++ b/lib/erl_docgen/src/docgen_otp_specs.erl
@@ -388,8 +388,10 @@ t_type([#xmlElement{name = nonempty_list, content = Es}]) ->
     t_nonempty_list(Es);
 t_type([#xmlElement{name = tuple, content = Es}]) ->
     t_tuple(Es);
-t_type([#xmlElement{name = map}]) ->
-    t_map();
+t_type([#xmlElement{name = map, content = Es}]) ->
+    t_map(Es);
+t_type([#xmlElement{name = map_field, content = Es}]) ->
+    t_map_field(Es);
 t_type([#xmlElement{name = 'fun', content = Es}]) ->
     ["fun("] ++ t_fun(Es) ++ [")"];
 t_type([E = #xmlElement{name = record, content = Es}]) ->
@@ -432,8 +434,11 @@ t_nonempty_list(Es) ->
 t_tuple(Es) ->
     ["{"] ++ seq(fun t_utype_elem/1, Es, ["}"]).
 
-t_map() ->
-    ["map()"].
+t_map(Es) ->
+    ["#{"] ++ seq(fun t_utype_elem/1, Es, ["}"]).
+
+t_map_field([K,V]) ->
+    [t_utype_elem(K) ++ " => " ++ t_utype_elem(V)].
 
 t_fun(Es) ->
     ["("] ++ seq(fun t_utype_elem/1, get_content(argtypes, Es),
@@ -550,6 +555,10 @@ ot_type([#xmlElement{name = nonempty_list, content = Es}]) ->
     ot_nonempty_list(Es);
 ot_type([#xmlElement{name = tuple, content = Es}]) ->
     ot_tuple(Es);
+ot_type([#xmlElement{name = map, content = Es}]) ->
+    ot_map(Es);
+ot_type([#xmlElement{name = map_field, content = Es}]) ->
+    ot_map_field(Es);
 ot_type([#xmlElement{name = 'fun', content = Es}]) ->
     ot_fun(Es);
 ot_type([#xmlElement{name = record, content = Es}]) ->
@@ -606,6 +615,12 @@ ot_nonempty_list(Es) ->
 ot_tuple(Es) ->
     {type,0,tuple,[ot_utype_elem(E) || E <- Es]}.
 
+ot_map(Es) ->
+    {type,0,map,[ot_utype_elem(E) || E <- Es]}.
+
+ot_map_field(Es) ->
+    {type,0,map_field_assoc,[ot_utype_elem(E) || E <- Es]}.
+
 ot_fun(Es) ->
     Range = ot_utype(get_elem(type, Es)),
     Args = [ot_utype_elem(A) || A <- get_content(argtypes, Es)],