Search Engines and Frames
Search engines have sometimes problems with frames! Frames might
make it impossible for a spider engine to find individual pages
of a website, or they lead visitors to the "inner section"
of a website without the respective frame context. This article
explains how you can prevent these problems.
Although more and more webmasters are leaving frames out, they
are still commonly used as a navigation and design feature for websites.
Let's look at a site with three frames: one for navigation, one
for the title and one for the actual content of the pages. The content
of the three frames is retrieved from three different pages, according
to the instructions saved on a fourth "master page", also
known as "frameset page". The HTML source text could for
example be as follows:
<head>
...
</head>
<frameset cols="50%,*" border="1">
<frame src="index.html" name="contentsframe">
<frameset rows="*,4*">
<frame src="header.html" scrolling="no"
name="headerframe">
<frame src="intro.html" name="bodyframe">
</frameset>
<noframes>
<body>
To view this page, you need a browser that supports
frames!
</body>
</noframes>
</frameset>
</html>
Most spider search engines however only see the respective master
page. Similar to an outdated browser, they simply do not understand
the instructions used for the assembly of the frame layout. The
frames are thus ignored. Only the information between the noframes
tags (i.e. data that is on the other hand ignored by a browser that
can interpret frames) is read. What would thus be read by a spider
engine that cannot handle frames? The result is surely not what
you would like it to be:
To view this page, you need a browser that supports frames!
This is not a very useful description of your page! Therefore,
we must offer a better description of our website to spider engines!
There is however an added problem: Within the noframes section,
there are no links to the other pages of your site, which means
that the spider engine cannot go beyond the master page. There might
be hundreds of pages packed with fascinating information on your
website. However, they are simply ignored, due to this simple error
and become thus invisible to many spider engines.
The NOFRAMES tag
The problem regarding the description can be solved by adding meta
tags to the master page. Meta tags provide however only a limited
solution for the problem, as they are not supported by all spider
engines. They are also no great help for visitors that wish to view
your pages with a browser that does not support frames. There is
though a solution available to tackle both problems by means of
intelligent design. Have a look at this example:
<head>
...
</head>
<frameset cols="50%,*" border="1">
<frame src="index.html" name="contentsframe">
<frameset rows="*,4*">
<frame src="header.html" scrolling="no" name="headerframe">
<frame src="intro.html" name="bodyframe">
</frameset>
<noframes>
<h2> My beautiful homepage.</h2>
If you can read this text, your browser does not support frames.
To access the pages of this website, go to the contents list and
click the respective links.
<a href="index.html">contents</a>
</body>
</noframes>
</frameset>
</html>
This example looks very similar to the initial page, provided that
it is not accessed by a spider engine or with an outdated browser.
To cater for these cases, the following additional data has been
entered in the noframes section:
My beautiful homepage. If you can read this text, your browser
does not support frames. To access the pages of this website, go
to the contents list and click the respective links.
Contents
...
The problems is solved. The pages do now contain text which can
be read by all spider engines, not just the ones that support meta
tags. In addition, we have provided a path for the visitors to access
the actual website by means of a link (index.html). To test the
above page, click this link. What you see next is the information
that is normally displayed in the navigation window. From here,
the spider engine can move on through the other pages of your site.
If you wish to position the noframes data close to the top of the
page, you can enter it immediately after the first framset tag.
Do not position the information before the first frameset tag, as
this would disable the frame information for Netscape Navigator.
Internet Explorer does in any case show the frames correctly.
Body tags within the noframes tags work with virtually all browsers.
You can thus rest assured that all browsers and spider engines that
might need the body tags can find them. Please remember to always
give a title to your frames, even if these titles are not displayed
in a correct frame context. For spider engines, titles are one of
the key indexing elements. Therefore, all pages should have a title.
Restoration of the frame context
There is one minor problem left to be solved: The spider engines
are now able to index the individual pages of your site. However,
visitors are not provided with the correct context, which means
that the pages will not be displayed in one of the three standard
frames. The page remains isolated, which can lead to problems. There
are webmasters that do not consider that pages are sometimes shown
outside the frame context. Such pages might therefore lack links
to other elements of the site, so that inexperienced surfers are
"caught" on the page. This might also occur, if you have
ignored all tips on how to make your website more accessible to
spider engines. The reason for this problem is that certain spider
engines such as AltaVista can handle frames. They browse through
your site while indexing every page, thus allowing visitors to access
pages without any context! There is however a very simple solution
available for this: All you have to do is to position a "home"
link at the bottom of each page. Have a look at this example:
<head>
...
</head>
<h2> CV </h2>
<a href="index.html" target="_top">homepage</a>
</body>
</html>
You should now see a page without frames as it would be viewed
by a visitor who has been brought there by a spider engine. The
only available link at the bottom of the page allows surfers to
go to your homepage, from where they can continue on using the frames.
Please ensure that this link contains a "target=_top"
string. Without this string, all visitors who have accessed your
pages by the "normal" route and who click the homepage
link, would otherwise obtain another 3-frame setup in the body frame.
Another solution is the inclusion of JavaScript. In the following
example, JavaScript is placed in the frame pages between the head
or the body tags:
<script language="JavaScript">
<!-- if (top == self) self.location.href = "NAME OF FRAMESET
PAGE"; // -->
</script>
Replace the section NAME OF FRAMESET PAGE with the name of your
master page that contains the frameset instructions. In this example,
the page name is index.html, and the script is thus as follows:
<script language="JavaScript">
<!-- if (top == self) self.location.href = "index.html";
// -->
</script>
Therefore: If your website contains frames, follow these
instructions to make your site easily available to both spider engines
and visitors who use older browser versions.
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