PCIe vs NVMe: Are They the Same?

Question - M2 x4 slot on B360 m 2 slot with pcie x4 lanes Client PCIe NVMe SSDs typically only use the 2280 form factor because its slim design allows it to easily fit into desktop and notebook PCs Enterprise- m2 pcie 40 in 30 slot So basically, I keep hearing that NVMe cards need 4x PCIe lanes But then I keep seeing posts saying that they can run at 2x lanes

m2 sata slot ; 22mm x 30mm, x2 or x4 lanes PCIe running the NVMe command set May be BGA mounted on MobileTablet LaptopPC boot Server boot ; 22mm x 80mm x4 lanes