I was looking at some photos and realizing how much perfboard I have used in recent years. I routinely find myself building small circuits, and that process almost always begins with grabbing a bit of perfboard from the supply stash.
The holes are usually about 0.042″ and will accommodate a wide range of electronic components without modification. Cheap perfboard will have no copper pads or traces, good perfboard will have a pattern of copper traces and pads to which you can solder your components. Better yet is perfboard with plated-thru holes and pads on both sides.