A:
Managed switches give you more control over your LAN traffic and offer advanced features to control that traffic. An unmanaged switch simply allows Ethernet devices to communicate with one another, such as a PC or network printer, and those are typically what we call “plug and play.”
Unmanaged versus Managed Switches - Cisco https://www.cisco.com/c/dam/en/us/products/switches/networking_solutions_products_genericcontent0900aecd806c7afe.pdf
Basically all these ports are the same, kinda like putting 5 straws into the same cup. everyone has the same opportunity to get the data whereas a manged switch allows you to set priority or control the data flow.
use this switch if your just need more ports, if your modem only has one prt but you need to hook up multiple devices..plug one port from this to the modem then all the remaining ports get the same data from the modem, basically just sharing the plug.