ATX (most commonly used today), BTX, LPX, NLX, backplane systems, and the outdated ATform factorpages 143-150 of A+ Guide to Managing & Maintaining Your PC, Sixth Edition by Jean Andrews
ATX is the form factor.
NICs stands for network interface controller. In computer networking, a NIC provides the hardware interface between a computer and a network. A NIC technically is network adapter hardware in the form factor of an add-in card such as a PCI or PCMCIA card.
The largest Form Factor was the EATX motherboard. The board measured 12 inches by 13 inches. Today the largest is the BAX motherboard which measures 10.5 inches by 12.8 inches.
The mother board, power supply, and chassis
The NLX form factor has a riser card on the edge of the motherboard.
atx,nlx,btx
Atx, btx, nlx
ATX
LPX form factor has no expansion slots but one slot in the middle of the board that allows it to host a bus riser card.The NLX has the same thing, however the expansion slot is at the end of the board. Also the NLX is standardized, unlike the LPX.
Form factor allowed for larger DIMM modules..and there a re designed to use ATX power supplies.
Case: minitowers:compact cases,low-profile cases or slimline cases. Power supply: ATX power supply
There are no similar form factors to ATX if you're talking about a slimline. Slimline form factors are NLX and LPX. The form factors to ATX are BTX, Micro-ATX, and Flex-ATX. There is no correlation between slimline and ATX.
NLX has slots parallel to the motherboard as ATX does not
NLx
The three form factors for desktop system boards are: ATX, and BTX and NLX
NLX, LPX, and Mini-LPX