A mesh network consists of multiple Wi-Fi devices or access points that act as if they were a single one. Instead of just one access point (when used in the home or very small businesses this is most often a wireless router), there are multiple points in the location. This has the advantage of having Wi-Fi cover a larger area with a stronger and more reliable signal. This means there will always be a strong and fast connection.
The larger the space the more access points would be used to provide blanket coverage. A mesh network differs from a wireless network repeater, as it does not require the devices accessing the network to switch over to a separate network. All the access points are connected and communicate with each other. This means is no need to switch networks that would potentially cause a delay in the Wi-Fi signal. Also, because the Access Points are connected, and adjust for demand, data routing is more efficient making flow faster.
Mesh networks are easy to expand, adding more access points means more reliability and better coverage over a wider area.
For business use, mesh networks have features like automatic rollover during failure. So that if one access point fails, the other units take over. With enough overlap, Wi-Fi will continue uninterrupted. With a single access point or a router, there is no redundancy. If it fails Wi-Fi is just no longer available. Some business products also have a heat map feature. This allows the person in charge of the wireless network to upload a floor plan. Then they view a map that shows which areas have low or obstructed coverage. Access points can be either added or relocated with this knowledge.
Mesh networks also have the benefit of being easier to manage. They can often be managed through a single pane of glass using a web interface or App to control the entire wireless network. Due to this control, it is easier to manage security. As well many mesh devices automatically check for and install firmware upgrades without intervention.
Mesh networks may not be the solution to every Wi-Fi setup, however, for covering a large area, without deceased performance, they are often the best solution.