Should css class names like 'floatleft' that directly describe the attached style be avoided?

Question

Lots of websites use class names like floatleft, clearfloat, alignright, small, center etc that describe the

Answer 1

There are two things that I feel get entirely left out of these discussions all too often. The first is WHY you would want to be all semantic or all not. The keywords are Branding and Skinning. Presentational class names may be justifiable if you work on some internal, departmental websites where branding and skinning will never in a million years get funding. On the other hand, customer facing sites, such as car manufacturers and department stores live in a world where every single new product that gets launched results in an entirely new skin for the website. New colors, new layout, new background images and all of this lead by designers who should be able to make the change purely in css so there's no chance they can break any working php (or what-have-you). There are also branded sites, where you have multiple skins, potentially running on the same site simultaneously. On sites with that requirement, you can't have visual changes impact html or you end up breaking every other brand just to update one of them. In these situations, semantic class names are a necessity.

The second thing that often gets left out is how to combat the problem of repeating groups of properties created by semantic class names, as in:

.content-nav {
    float: left;
    margin-right: 10px;
    background-color: #ccc;
}

.content-nav .user-photo {
    float: left;
    margin-right: 10px;
    border: solid 1px #000;
}

.content-nav .user-display-name {
    float: left;
    margin-right: 10px;
    text-decoration: underline;
}

People often point this out as a drawback of semantic names, and I think that that's a valid point. On the other hand I would like to point out that there are tools that can help you keep semantic css DRY, such as LESS and SASS. I did see one other commenter mention this above, but I just thought that this point was worth highlighting.