What is a NVMe SSD and How Fast is it?

NVMe SSD nvme m 2 slot laptop I'm keeping the one that the laptop came with: Samsung SSD 256GB PM991, which my Windows 10 is installed on, but I'm buying one since I don't nvme pcie 40 in 30 slot The dell manual says it's SATA PCIe The laptop had a 2280 SSD with 1 2 notches and was working fine but after a bunch of years

nvme m2 ssd slot Switch off your device and as a safety precaution plug it out Open your system and locate the PCIe slot On the motherboard locate the interface