Can one leave out the www?

[Jane Here]

In my browser I can type a web site as:

http://xxx.com

or

http://www.xxx.com

When I want to put a link into an html page, which syntax is recommended? Or
are both OK?

 

[David Berry]

You should use the WWW. If it's a link on your own site then you'd use a
relative URL not an absolute one (/docs/mypage.htm as opposed to
http://www.xxx.com/docs/mypage.htm)

Whether or not you need to type a WWW is up to the web hosting company.
Some companies will create an alias for your site where xxx.com works and
some require the www.xxx.com