The most useful screwdriver knowledge is matching the driver shape to the screw head correctly so the tool seats fully and does not strip the fastener under pressure.
For small home jobs, screw size is mostly about length, thickness, and whether the fastener matches the material, load, and pilot hole rather than about one universal best number.
The main screw families matter because wood screws, machine screws, and sheet metal screws are built to grip different materials and fail in different ways when swapped carelessly.
Stripped screw removal works best when the first steps focus on restoring grip and reducing pressure on the surrounding surface instead of escalating immediately to destructive force.
Wall anchor choice changes with wall material because drywall, plaster, and masonry fail differently and demand different drilling, expansion, and holding logic.