What is PCIe , and how is it different from previous generations?

What is PCIe , and how is it different from previous generations? pcie 5 0 x16 slot or;3 PCIe x16 Slots + 2 PCIe x8 Slots or;2 PCIe x16 Slots + 4 PCIe 1 PCIe x16 FHFL double-width slot 1 PCIe x16 AIOM slot pcie 30 x4 slot In ASUS 「PCIe x16 Slots - 5」

pcie 30 x4 slot The number of lanes depends upon the slot size: x1 slots have one lane, x4 slots have four lanes, x8 slots have eight lanes, and x16 slots have

pcie slot bracket PCIe NVMe and SAS storages with optional RAID; two PCIe Riser cards supporting high speed interface; PCIe to AIOM slot X14DBT-B · Learn more  PCIe Two Slot Backplane · PCIe Three Slot Backplane · PCIe Five Slot PCIe x16 Transparent Host Target Adapter The MXH532 x16 PCIe