I was working on a relatively simple layout recently, but got confused when Gecko added a small gap under an image that wasn't there in Safari. I messed around some and got it down to a simplified testcase that told me it's in some way related to an inline image getting line spacing below it. Here's an example: http://steelbluepanic.com/temp/funny-margin-testcase.html (That's a white blank png in a DIV, margins and padding of both set to zero, red lines added to illustrate.) In my layout all I needed to do was set the img to display as block, at which point everything was nifty. But I like to know why. I'm sort of guessing this is because the image is treated as if it's sitting on the baseline of a line of text, and so there's a gap below for the descenders; anybody know if this is correct, or is there something else I'm not understanding? Also, I'm weirded out by the fact that with my more complex layout it did NOT leave that gap in Safari, but did in Camino. Since my simplified testcase DOES show the gap in Safari as well, they were obviously interpreting some inherited style differently, which is odd because I wasn't doing anything that complicated, and I don't see what I could have done to the containing elements (not much) to cause it to leave off that space in Safari. Any standards gurus wanna point me in the direction of enlightenment?