Help! I cannot get a transparent background for my logo created in Illustrator!

I am ready to pull my hair out!  No matter what I do, I cannot get a transparent backround for a logo that I am trying to create in Illustrator.  I have saved it for Web export, check marked the transparent box and whatnot, but when I go to use it on a webpage, a light grey box shows around it!  When I saved it, it had the typical checkered background so I have no idea where this is coming from!  I inserted the image into a Word document just to see if the same would happen there.  Guess what?  The background was transparent-even on a colored background!  I am watched every darn video on YouTube concerning transparent backgrounds and still can't seem to figure out what I am doing wrong!  If anyone can help, I would be forever grateful!  BTW, I am fairly new to Illustrator (obviously )