Eventing is major part while upgrading to business central, we face alot of customisation done in Customer database which needs to be evented and converted into extension.
Source : Divyesh Chitte
The following Microsoft Dynamics NAV clients interact with the Microsoft Dynamics NAV database through Microsoft Dynamics NAV Server:
•Microsoft Dynamics NAV Windows client
•Microsoft Dynamics NAV Web client
Bron : Mohana’s Dynamics NAV Blog