Hollow wall anchors are used for medium-duty applications. They'll normally add permanent screw threads to any material to which they're attached. These types of anchors also expand as the screw is tightened and driven into the cavity. This anchor can be installed using a hammer or a drill and can be used with various wall thicknesses. These anchors are also sometimes known as Molly bolts, and their maximum holding load is about 50 pounds.
Expansion anchors are used with concrete, masonry, and more. They're designed to spread open once they're anchored, thus their name. This provides a stronger hold. The three basic styles of wedge anchors are fully threaded, partially threaded, and the full-bodied wedge anchor. Plastic expansion anchors are the most commonly used anchor type. The more heavily "ribbed" anchors will give the greatest gripping strength regardless of the wall material.
2) Hollow-wall anchors, on the other hand, will not work in solid materials. Instead, they are designed to be used in thin materials or on hollow walls. They each have a unique way of spreading within the hollow of the wall. Once spread, the anchor cannot be pulled back through the smaller installation hole.
Drywall anchors are a plastic sleeve inserted into the wall where no stud is available. They spread out behind the drywall, once a screw is inserted, to provide stability and extra support for the items hung on the wall. The spreading makes larger anchors difficult to remove without cutting out a larger section of the wall.
Threaded Drywall Anchors Known by the trade names such as EZ-Ancor (not a typo!!)or Zip-It, this type of anchor is a basically a large, outside-threaded nut with a point on the end! The large threads are intended to hold strongly into drywall and will accept #6 or #8 sheet metal screws.