Information Technology Reference
In-Depth Information
META tags live in the
head
section of an HTML page, and generally have two elements,
the name of the element, and the value. For example, the following value specifies the
keywords associated with the particular webpage:
<
meta
name="keywords" content="android, howto, information" >
A Little META History
Back when search engines first began indexing the Internet, they used the keywords
and description
META
elements to understand what a given webpage was all about. In
the late 1990s, full-text search engines (such as Google) began indexing and using all of
the text of a given webpage to determine what the page contained, and these
META
elements became less important. In fact, an entire industry had sprung up purporting to
help web page owners get more traffic by “optimizing” their web pages, which usually
included updating the
META
elements search engines used. This industry of “search
engine optimization,” or SEO, still exists today and is in fact a very cutthroat type of
business, although many search engines look for the older “tricks” used and may
penalize pages for using them today. For example, one trick used was known informally
as “keyword stuffing”, which was what it sounded like—stuffing the
META
keyword
element with many different terms, some of which may score highly to search engines
but weren't exactly accurate in regards to the page's actual content. Modern day SEO
firms must rely on a number of other techniques to increase a page's search rank,
including a number of things we don't normally consider as designers (e.g., what links
are on the page, page titles, layout, wording, etc…).
One of the interesting things about
META
tags is that there are considerably fewer
“official”
META
tags than the total that exist on the web. Various software companies that
produce web browsers, such as Microsoft, may decide to build their browser to detect
“unofficial”
META
tags and respond to them.
For example, Microsoft pioneered the use of the MobileOptimized
META
tag, which told
its mobile internet browser (Pocket Internet Explorer or Internet Explorer Mobile) how to
specially render a page that used this tag. Some non-Microsoft produced browsers
supported the tag, but no guarantee could be made that the tag would help users of
rival browsers as much as it did users of Internet Explorer. Similarly, our old friend
AvantGo, mentioned earlier, used a tag named HandheldFriendly for much the same
purpose, with the same problems associated.
The Viewport Element
All of this confusion, rivalry, and non-conforming led to the introduction and fairly wide
acceptance of a new
META
element known as Viewport that, while still unofficial, is the
most current “special”
META
tag of interest to mobile developers. The Viewport can be
thought of as a window on top of a web page. Sometimes the entire web page fits into
the window, and other times we want to size the window differently, depending on how
we build the page. One reason that the Viewport tag has been a bit more successful