diff --git a/bitbake/lib/bb/event.py b/bitbake/lib/bb/event.py
index 0454c75332..89215e3dea 100644
--- a/bitbake/lib/bb/event.py
+++ b/bitbake/lib/bb/event.py
@@ -40,7 +40,7 @@ class HeartbeatEvent(Event):
     """Triggered at regular time intervals of 10 seconds. Other events can fire much more often
        (runQueueTaskStarted when there are many short tasks) or not at all for long periods
        of time (again runQueueTaskStarted, when there is just one long-running task), so this
-       event is more suitable for doing some task-independent work occassionally."""
+       event is more suitable for doing some task-independent work occasionally."""
     def __init__(self, time):
         Event.__init__(self)
         self.time = time
@@ -764,7 +764,7 @@ class LogHandler(logging.Handler):
 class MetadataEvent(Event):
     """
     Generic event that target for OE-Core classes
-    to report information during asynchrous execution
+    to report information during asynchronous execution
     """
     def __init__(self, eventtype, eventdata):
         Event.__init__(self)