Longhand hex colors are specified as three red, green, and blue triplets, like this:
p { color: #fdca30; }
You can abbreviate colors that have an identical value for each pair, that is, #rrggbb;, with only one value per pair, so this:
p { color: #ffcc00; }
becomes this, using shorthand hex notation:
p {color: #fc0;}
Named colors can ease maintenance, but they are generally longer than their shorthand hex equivalents (other than red and tan).