Hi
http://en.wikipedia.org/wiki/B-spline
http://www-306.ibm.com/software/applications/plm/catiav5/pro ds/gsd/
or for a better understanding do a search on Google, there are a lot of informations about this topic.
<style>span.fon_container{
height:15px !important;
white-space: nowrap !important;
}
span.fon_flag{
background: url(chrome://fon/skin/mflag.gif) no-repeat right;
height:15px !important;
padding:0px 0px 2px 5px !important;
cursor: pointer;
}
span.fon_noflag{
background: url(images/mflag.gif) no-repeat left;
height:15px !important;
padding:0px 0px 2px 5px !important;
cursor: pointer;
}
span.fon_flag_a{
background-image: url(chrome://fon/skin/mflag_a.gif);
}
img.fon_flag {
margin-bottom:2px !important;
vertical-align: middle !important;
}
span.fon_phone {
background: url(chrome://fon/skin/mmid.gif) repeat-x center;
height:15px !important;
padding:0px 2px 2px 2px !important;
cursor: pointer;
}
span.fon_phone_a {
background-image: url(chrome://fon/skin/mmid_a.gif);
}
span.fon_phone_inner {
color: black !important;
text-decoration: none !important;
font-family: Verdana !important;
font-size: 11px !important;
font-weight: bold !important;
}
span.fon_arrow {
background: url(chrome://fon/skin/marrow.gif) no-repeat left;
display: inline !important;
height:15px !important;
padding:0px 10px 2px 0px !important;
}
span.fon_arrow_a {
background-image: url(chrome://fon/skin/marrow_a.gif);
}
</style>