how to specify image size in pixels

Question

Quick question about specifying the size of images in pixels:

<img src="/logo.jpg" alt="logo" width="200px" height="120px" />

or

<img src="/logo.jpg" alt="logo" width="200" height="120" />

I've been always putting in the px but recently noticed that very few people do this. Am I better off leaving that out? Does it matter one way or the other?

Answer 1

Use css to consider the the size of the image:

CSS:

.logo {
width: 200px;
height: 120px;
}

HTML:

<img src="/logo.jpg" alt="logo" class="logo" />