Headboards - all the same size?

[Cass168]

So... I bought a bed in the m&s sale a few months ago when ours broke. Didn't come with a headboard and as we are planning to decorate anyway next year I thought I'd pick one up at a later date.
I've just had a look on the m&s website and I don't really like any of their own headboards, so could I just buy one from somewhere else? Would it fit?
Sorry if that's a silly question but I've only ever had wooden beds before!

[wowfudge]

Some headboards are fitted to the wall rather than the bed. The ones that fit over the screws on the bed head will have a standard distance between the struts, but you can measure this to be sure.