HTML and CSS Reference
In-Depth Information
however, some browsers might have problems with them and not recognize the pathname
correctly. For full compatibility with all browsers, use
%20
, as follows:
CAUTION
If you make sure that your file and directory names are short and
use only alphanumeric characters, you won't need to include spe-
cial characters in URLs. Special characters can be problematic in a
variety of ways. When you're creating your own pages, you should
avoid using spaces in file names as well as other non-alphanumeric
characters whenever possible.The two exceptions are _ and -, which
are the preferred separators between words in URLs.
Additional Attributes for the
<a>
Tag
There are some additional attributes for the
<a>
tag that are less common. These offer the
following:
tabindex
—Supports a tabbing order so that authors can define an order for
anchors and links, and then users can tab between them the way they do in a dialog
box in Windows or the Mac OS.
n
Event handlers such as
onclick
,
onfocus
, and
onblur
—The full list of events is
included in the section “ Global Attributes and Events “ of Appendix B. You'll
learn how to use these attributes on Lesson 14, “Introducing JavaScript.”
n
Many kinds of URLs are defined by the Uniform Resource Locator specification. (See
Appendix A, “Sources of Further Information,” for a pointer to the most recent version.)
This section describes some of the more popular URLs and some situations to look out
for when using them.
6
HTTP
HTTP URLs are by far the most common type of URLs because they point to other doc-
uments on the Web. HTTP is the protocol that World Wide Web servers use to communi-
cate with web browsers.
HTTP URLs follow this basic URL form:
