Normally now a day’s user adds Skype toolbar to their browser and this makes your contact no highlighted with Skype icon and its colour. This is not good for your site as it may affect you design and your site will not look like what you made it.
There are several ways to prevent your site from Skype toolbar but all of them are very time wasted as they all say you to write extra code when you write your contact number.
My suggestion is to use simple Meta tag in your header file to disallow the Skype toolbar to highlight the contact number and to prevent your design to look ugly.
Add this in your header:
<meta name=”SKYPE_TOOLBAR” content =”SKYPE_TOOLBAR_PARSER_COMPATIBLE”/>
Advantage of this single line is that you don’t have to make changes at all the places where you have written your contact number.