What's the difference between a multi-bit ratcheting screwdriver and a bitholding ratchet?

Multi-bit drivers (like the Klein 32305 or Megapro Original) store a set of double-ended bits inside the handle and pop them out as needed. Bitholding ratchets (like the Wera RA-R) are slimmer and accept standard 1/4-inch bits but rely on you supplying your own bit set. Multi-bit tools are more self-contained; bitholders are lower-profile and more flexible if you already own bits.