See section /* Common Classes */ of this page.

http://webdesign.about.com/od/css/a/master_stylesht_2.htm

are these css classes good, to use in any project? in terms of semantic?

/* Common Classes */

.clear { clear: both; }

.floatLeft { float: left; }

.floatRight { float: right; }

.textLeft { text-align: left; }

.textRight { text-align: right; }

.textCenter { text-align: center; }

.textJustify { text-align: justify; }

.blockCenter { display: block; margin-left: auto; margin-right: auto; } /* remember to set width */

.bold { font-weight: bold; }

.italic { font-style: italic; }

.underline { text-decoration: underline; }

.noindent { margin-left: 0; padding-left: 0; }

.nomargin { margin: 0; }

.nopadding { padding: 0; }

.nobullet { list-style: none; list-style-image: none; }