I'm looking up publishers, trying to find someone to send my manuscript to. However, when I was looking I found that almost everywhere I look they requested that the manuscript be double spaced. However, I don't have a clue what this means; even my Mum doesn't know.
So, I decided that I would ask here, see if anybody knows. Please?

I seriously have no idea about it, other than almost all writing programs have an option to write in double-spaced format. I assume it's...double spaced? Two spaces? Either that or it has to do with the line spacing. That's the part I've noticed about it. <.<

Double spacing is essential for publishers as it makes the work far easier to read. There should be an option in your Word program. I use Microsoft Office Word 2007, and my spacing button is next to the text alignment buttons.

Thanks, I'll check that out later

If you can't find the button, highlight all of your text and "Format" dropdown, then choose "Paragraph." Where it says "line spacing," you can choose double. In my experience, in almost all settings where text is looked at analytically, be it in a publishing environment or a school setting, double spacing is requested because it makes it easier to write in the margins.