Read this next to the computerized vs mechanical compare and the shop.
What the listing is saying
Brother lists the CS7000X with seventy built-in stitches, an LCD, a wide table, and ten feet in the box. Singer lists the 4452 as a heavy-duty mechanical with thirty-two stitches and extra piercing power for denim and canvas. Singer lists the 7258 Stylist as a computerized machine with one hundred stitches and ten feet.
Those numbers are manufacturer copy on the product page. If a later revision changes the count, the listing wins.
Computerized
A computer picks the stitch from a panel or a screen. Buttonholes often run in one step. Decorative stitches sit in memory. The CS7000X and the 7258 live here. You trade a few more menus for stitch variety you do not have to cam in by hand.
Mechanical
A dial or a lever sets the stitch. The 4452 is this kind of machine. Fewer programs, a metal frame on that listing, and a straight path when the cloth is heavy. You do not get seventy stitches. You get the ones on the dial, and they are the ones you will actually use.
Get this on the shop cards opens the product page for each machine.