If your company has enabled broadcast from the Admin Panel, a job can be sent out or broadcast to all suitable vehicles. The vehicles will then have the option to accept or decline within a time limit. This is in contrast to auto-dispatching, which will only offer the job to the best vehicle.
Once you and other drivers accept the offer, the system will then determine who wins the bid. This selection is based on factors that can be chosen from the Dispatch Settings in the Admin Panel, for example the closest vehicle, or the one that has waited the longest (first in zone queue).
You can find more information in the Offers tab. Here you will see the offers you have already accepted, as well as the bids that you have either won or lost.