diff --git a/src/multiplayer.ts b/src/multiplayer.ts
index 2f3b283..6f9db8c 100644
--- a/src/multiplayer.ts
+++ b/src/multiplayer.ts
@@ -27,6 +27,10 @@ const configuration: RTCConfiguration = {
   ],
 };
 
+type Message = {
+  type: "HeartBeat" | "GameState" | "UpdatePosition";
+};
+
 export async function initWebRTC(peerId?: string) {
   const peer = new Peer({
     config: configuration,
@@ -36,7 +40,7 @@ export async function initWebRTC(peerId?: string) {
     console.log(`Connection received from: ${conn.peer}`);
 
     conn.on("open", () => {
-      conn.on("data", (data) => {
+      conn.on("data", (data: Message) => {
         console.log(`Data: ${data}`);
       });
 
@@ -52,7 +56,7 @@ export async function initWebRTC(peerId?: string) {
       const conn = peer.connect(peerId);
 
       conn.on("open", () => {
-        conn.on("data", (data) => {
+        conn.on("data", (data: Message) => {
           console.log(`Data: ${data}`);
         });