Method of sharpening knives with steel

Question

The following is an extract from 'How to Cook Everything' by 'Mark Bittman' about sharpening knives:

An electric sharpener is the best, easiest, and most expensive way to keep knife blades sharp; even moderately serious cooks should consider this a worthwhile investment. The alternatives are to learn to use a whetstone (not that difficult, and very effective, but timeconsuming) or to take them to a hardware store to have them sharpened professionally. A steel is a handy tool for maintaining the edge of knives between sharpenings. (You should use it every few days, at least.) It’s nothing more than a sturdy rod stuck in a handle, but it takes some practice to get the hang of it

Firstly, this addresses how we could sharpen knives - an electric sharpener or whetstone do the same job of sharpening. Then it mentions that a (sharpening) steel helps in maintaining the edge of the knives between sharpenings.

Does this mean that, in order to sharpen knives, we need an electric sharpener/whetsone and a sharpening steel? Can we just use a sharpening steel to sharpen knives - why?

Sorry if this seems like a silly question. I've not been taught anything about sharpening knives, and only know of its practice. My understanding is that we can sharpen knives using either a sharpening steel, or a whetstone. I've never heard anything about 'maintaining the edge of knives between sharpenings' as Mr Bittman states in his book

Answer 1

A steel is used to realign the edge, allowing it to slice cleanly. Sharpening a blade removes metal to produce a new edge on a dull blade. The process of realigning the edge is also called 'honing'. My electric shapener has three slots to perform various levels of sharpening. One of them is just to hone the knife. The steel rod with a handle that comes with most knife sets serves the same purpose.

Answer 2

The process that he's talking about is called 'honing'.

Basically, as you use your knife, there's a chance for the edge of the knife to go slightly out of alignment. If you continue to use it like this, it just won't cut as well.

'Sharpening' involves grinding off metal to re-form the edge. 'Honing' is more like pushing the edge back into place (you might grind off a little bit of metal, but significantly less)

The thing is, the more rushed that you are, and the more aggressive with your knife, the more often that you'll want to hone it. Cutting hard things can be a problem if you're not coming at it perfectly straight. It's also important to not use hard cutting boards -- stone, glass, etc, as that will quickly ruin your edge.