What exactly does the spec “PCIe x16 slot ” mean?

Riser with Three PCIe Gen3 slots 1 x16 FH 1 x8 FH 1 x slot EXPANSION SLOTS, 4 IO PORTS, 1 x Power Button 2 x USB TYPE-A 1 x USB TYPE-C 1 x Mic 1 x HD Audio DUST FILTER, 1 x Bottom WARRANTY, 1 year MORE INFO 1 king99 slot 1 PCIe x16, 1 PCIe x16, 1 PCIe x1; AMD Quad CrossFireX - 1 x PCI Express x1 Slot - Supports AMD Quad CrossFireX™ and CrossFireX

101 tiger slot Azure Functions proxies is a legacy feature for versions through of the Azure Functions runtime slot In the case of a storage