| Synchronous Events | Asynchronous Events |
| This event fires before the actual event does. | This event fires after the actual event. |
| It helps in getting the HttpContent. | We cannot get the HttpContent. |
| The error message can be displayed. | The error message cannot be displayed. |
| This event can be cancelled. | This event cannot be cancelled. |
| Synchronous methods end with "ing" such as itemadding, itemupdating itemdeleting. | Asynchronous methods end with "ed" such as itemadded, itemupdated, itemdeleted. |