diff --git a/README.md b/README.md
index 36c96d1..9cb50dc 100644
--- a/README.md
+++ b/README.md
@@ -62,7 +62,15 @@ This go-firebase-admin SDK supports the following functions :
   * not documented
   
 - Cloud Messaging API
-  * TODO
+  * SendToDevice : Send Message to individual device
+  * SendToDevices : Send multicast Message to a list of devices
+  * SendToDeviceGroup : Send Message to a device group
+  * SendToTopic : Send Message to a topic
+  * SendToCondition : Send a message to devices subscribed to the combination of topics
+  * SubscribeDeviceToTopic : TODO
+  * SubscribeDevicesToTopic : TODO
+  * UnSubscribeDeviceFromTopic : TODO
+  * UnSubscribeDevicesFromTopic : TODO
 
 To-Do List
 ----------
diff --git a/fcm.go b/fcm.go
index 8b126c9..9c89de0 100644
--- a/fcm.go
+++ b/fcm.go
@@ -37,7 +37,7 @@ func (fcm *FCM) SendToDevice(registrationToken string, payload Message) (*Respon
 	return fcm.sendFirebaseRequest(payload)
 }
 
-// SendToDevices Send multicast Message to devices
+// SendToDevices Send multicast Message to a list of devices
 // see https://firebase.google.com/docs/cloud-messaging/admin/send-messages#send_to_individual_devices
 func (fcm *FCM) SendToDevices(registrationTokens []string, payload Message) (*Response, error) {
 
@@ -58,7 +58,7 @@ func (fcm *FCM) SendToDeviceGroup(notificationKey string, payload Message) (*Res
 	return fcm.SendToDevice(notificationKey, payload)
 }
 
-// SendToTopic TODO NOT IMPLEMENTED
+// SendToTopic Send Message to a topic
 // see https://firebase.google.com/docs/cloud-messaging/admin/send-messages#send_to_a_topic
 func (fcm *FCM) SendToTopic(notificationKey string, payload Message) (*Response, error) {
 	return fcm.SendToDevice(fmt.Sprint("/topic/", notificationKey), payload)