What is event bubbling?
Server controls like Datagrid, DataList, and Repeater can have other child controls inside them.
Example DataGrid can have combo box inside datagrid. These child control do not raise there
events by themselves, rather they pass the event to the container parent
(which can be a datagrid,datalist, repeater), which passed to the page as
“ItemCommand” event. As the child control sendevents to parent it is termed as event bubbling.
.NET Interview Questions 4 th Edition By Shivprasad Koirala