diff --git a/RxJava/practice/src/main/java/org/example/ex03/ColdPublisherEx.java b/RxJava/practice/src/main/java/org/example/ex03/ColdPublisherEx.java
new file mode 100644
index 00000000..15a42b3b
--- /dev/null
+++ b/RxJava/practice/src/main/java/org/example/ex03/ColdPublisherEx.java
@@ -0,0 +1,13 @@
+package org.example.ex03;
+
+import io.reactivex.rxjava3.core.Flowable;
+
+public class ColdPublisherEx {
+
+    public static void main(String[] args) {
+        Flowable<Integer> flowable = Flowable.just(1, 3, 5, 7);
+
+        flowable.subscribe(data -> System.out.println("구독자1: " + data));
+        flowable.subscribe(data -> System.out.println("구독자2: " + data));
+    }
+}
diff --git a/RxJava/practice/src/main/java/org/example/ex03/HotPublisherEx.java b/RxJava/practice/src/main/java/org/example/ex03/HotPublisherEx.java
new file mode 100644
index 00000000..b137ed40
--- /dev/null
+++ b/RxJava/practice/src/main/java/org/example/ex03/HotPublisherEx.java
@@ -0,0 +1,19 @@
+package org.example.ex03;
+
+import io.reactivex.rxjava3.processors.PublishProcessor;
+
+public class HotPublisherEx {
+
+    public static void main(String[] args) {
+        PublishProcessor<Integer> processor = PublishProcessor.create();
+        processor.subscribe(data -> System.out.println("구독자1: " + data));
+        processor.onNext(1);
+        processor.onNext(3);
+
+        processor.subscribe(data -> System.out.println("구독자2: " + data));
+        processor.onNext(5);
+        processor.onNext(7);
+
+        processor.onComplete();
+    }
+}