Difference between PCI and PCI express

I am assuming slot that you refer to is NVMe interconnect, because on an SATA it is SATA, nothing more NVMe is a PCIe in

What Are Small PCIe x1 Slots? PCIe x1 Slots are the smallest of the four PCIe slot standards for motherboards! These slots may not always be present on your

slot casino slot machines 1x adapter PCI-E card can be inserted in any PCI-E Slot: 1x, 4x, 8x, or 16x; Support 2 port high speed PCIe 1X card; 1-slot PCI-E 1X to 2 slot 1X riser card

slot 101 Most commonly, PCIe expansion slots are used for the add-in graphics card, SSD storage devices, Wi-Fi adapters, and other sorts of expansions