Hyper Text Markup Language (HTML) Interview Preparation Guide

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Search engines can link directly to framed content documents, but they cannot link to the combinations of frames for which those content documents were designed. This is the result of a fundamental flaw in the design of frames.
Search engines try to provide their users with links to useful documents. Many framed content documents are difficult to use when accessed directly (outside their intended frameset), so there is little benefit if search engines offer links to them. Therefore, many search engines ignore frames completely and go about indexing more useful (non-framed) documents.
Search engines will index your <NOFRAMES> content, and any content that is accessible via your

The only way to have a frame with a vertical scrollbar but without a horizontal scrollbar is to define the frame with SCROLLING="auto" (the default), and to have content that does not require horizontal scrolling. There is no way to specify that a frame should have one scrollbar but not the other. Using SCROLLING="yes" will force scrollbars in both directions (even when they aren't needed), and using SCROLLING="no" will inhibit all scrollbars (even when scrolling is necessary to access the frame's content). There are no other values for the SCROLLING attribute.

If there is no existing frame with the name you used for the TARGET attribute, then a new browser window will be opened, and this window will be assigned the name you used. Furthermore, TARGET="_blank" will open a new, unnamed browser window.
In HTML 4, the TARGET attribute value is case-insensitive, so that abc and ABC both refer to the same frame/window, and _top and _TOP both have the same meaning. However, most browsers treat the TARGET attribute value as case-sensitive and do not recognize ABC as being the same as abc, or _TOP as having the special meaning of _top.
Also, some browsers include a security feature that prevents documents from being hijacked by third-party framesets. In these browsers, if a document's link targets a frame defined by a frameset document that is located on a different server than the document itself, then the link opens in a new window instead.

If Microsoft Internet Explorer displays your document normally, but other browsers display your plain HTML source, then most likely your web server is sending the document with the MIME type "text/plain". Your web server needs to be configured to send that filename with the MIME type "text/html". Often, using the filename extension ".html" or ".htm" is all that is necessary. If you are seeing this behavior while viewing your HTML documents on your local Windows filesystem, then your text editor may have added a ".txt" filename extension automatically. You should rename filename.html.txt to filename.html so that Windows will treat the file as an HTML document.

They are a few reasons that this could happen. The most common are:

1. You're attempting to use a .bmp or .tif or other non-supported file format. You can only use .gif and .jpg on the web. You must convert files that are not .gif or .jpg into a .gif or .jpg with your image/graphics program.
2. You've forgotten to upload the graphic files. Double-Check.
3. You've incorrectly linked to the images. When you are starting out, try just using the file name in the <img> tag. If you have cat.jpg, use
img src="cat.jpg">.
4. Image file names are case-sensitive. If your file is called CaT.JpG, you cannot type cat.jpg, you must type CaT.JpG exactly in the src.
5. If all of the above fail, re-upload the image in BINARY mode. You may have accidentally uploaded the image in ASCII mode.

Yes. This is part of HTML 2.0 Forms support (some early browsers did not support it, but browser coverage is now excellent).
The submit buttons must have a NAME attribute. The optional VALUE attribute can be used to specify different text for the different submit buttons.
To determine which submit button was used, you need to use different values for the NAME and/or VALUE attributes. Browsers will send to the server the name=value pair of the submit button that was used. Here is an example:

<input type="submit" name="join" value="I want to join now">
<input type="submit" name="info" value="Please send full details">

Note that if you are using image submit buttons, you need to provide different NAME attributes for them too. Also, browser behavior can be inconsistent when the form is submitted without a submit button (e.g., by hitting ENTER).
If you're unsure what results you're going to get when you submit your form, TipJar has a standard script which you can use. Code this, for example (assuming method "post"):

<form method="post" action="http://www.yoursite.com/cgi-bin/test">
and then go through the motions of submitting your form. The TipJar server decodes the form input, and displays the result to you.

When the sub-documents of a frameset state are accessed directly, they appear without the context of the surrounding frameset.
If the reader's browser has JavaScript support enabled, the following script will restore the frameset:

<SCRIPT TYPE="text/javascript">
if (parent.location.href == self.location.href) {
if (window.location.href.replace)
window.location.replace('frameset.html');
else
// causes problems with back button, but works
window.location.href = 'frameset.html';
}
</SCRIPT>
A more universal approach is a "restore frames" link:

<A HREF="frameset.html" TARGET="_top">Restore Frames
Note that in either case, you must have a separate frameset document for every content document. If you link to the default frameset document, then your reader will get the default content document, rather than the content document he/she was trying to access. These frameset documents should be generated automatically, to avoid the tedium and inaccuracy of creating them by hand.
Note that you can work around the problem with bookmarking frameset states by linking to these separate frameset documents using TARGET="_top", rather than linking to the individual content documents.

There was atag proposed for HTML 3.0, but it was never adopted by any major browser and the draft specification has now expired. You can simulate a tab or indent in various ways, including using a transparent GIF, but none are quite as satisfactory or widely supported as an official tag would be.

Because copies of your HTML files and images are stored in cache, it is impossible to prevent someone from being able to save them onto their hard drive. If you are concerned about your images, you may wish to embed a watermark with your information into the image. Consult your image editing program's help file for more details.

You will need to use the below meta tag.
<META HTTP-EQUIV="Refresh" CONTENT="2"; URL="http://www.yourname.com">
Placing the above tag in your <HEAD></HEAD> will load yousite.com in 2 seconds.
Changing the 2 value on CONTENT="2" to another value will increase or decrease the delay until loading the new page.

For older versions of Internet Explorer, this technique was used <BG SOUND="sound.ext">.

The method parameter specifies which method the client is using to send information to the WEB server. The method determines which parameter you will find the CGI request data in:

► POST - post_args
► GET - http_search_args

You're probably looking at the wrong part of the screen. The Title usually shows up in the Title Bar on the Window, to the left of the minimize/maximize buttons on graphical browsers.

1: Plaintext or any text information viewable from your browser can be easily copied like any other text from any other file.
2; HTML and web scripts - you will need to view the web page's source code. In the page's source code, copying the <script> and </script> tags as well as all the information in-between these tags will usually enable the script to work on your web page.
3: Images, sounds, or movies - Almost all images, sounds, and movies can be copied to your computer and then viewed on your webpage. Images can be easily copied from a webpage by right-clicking an image and selecting "Save Picture as" or "Save Image as". Unless the sound or movies file has a direct link to download and save the file to a specified location on your hard disk drive or to view your Internet browser's cache and locate the sound or movie file saved in the cache.
4. Embedded objects - Looking at the source code of the object to determine the name of the file and how it is loaded, and copy both the code and the file.

Older versions of Netscape Navigator seems to convert pixel-based frame dimensions to whole percentages, and to use those percentage-based dimensions when laying out the frames. Thus, frames with pixel-based dimensions will be rendered with a slightly different size than that specified in the frameset document. The rounding error will vary depending on the exact size of the browser window.
Furthermore, Navigator seems to store the percentage-based dimensions internally, rather than the original pixel-based dimensions. Thus, when a window is resized, the frames are redrawn based on the new window size and the old percentage-based dimensions.
There is no way to prevent this behavior. To accomodate it, you should design your site to adapt to variations in the frame dimensions. This is another situation where it is a good idea to accomodate variations in the browser's presentation.

"Getting framed" refers to having your documents displayed within someone else's frameset without your permission. This can happen accidentally (the frameset author forgot to use TARGET="_top" when linking to your document) or intentionally (the frameset author wanted to display your content with his/her own navigation or banner frames).

To avoid "framing" other people's documents, you must add TARGET="_top" to all links that lead to documents outside your intended scope.
Unfortunately, there is no reliable way to specify that a particular document should be displayed in the full browser window, rather than in the current frame. One workaround is to use <BASE TARGET="_top"> in the document, but this only specifies the default target frame for links in the current document, not for the document itself.

If the reader's browser has JavaScript enabled, the following script will automatically remove any existing framesets:

<script type="text/javascript">
if (top.frames.length!=0) {
if (window.location.href.replace)
top.location.replace(self.location.href);
else
top.location.href=self.document.href;
}
</script>

An alternative script is

<script type="text/javascript">
function breakOut() {
if (self != top)
window.open("my URL","_top","");
}
</script>
</HEAD>
<BODY onLoad="breakOut()">

There is no way in standard HTML to specify where page breaks will occur when printing a page. HTML was designed to be a device-independent structural definition language, and page breaks depend on things like the fonts and paper size that the person viewing the page is using.

This is best done with a small form:

<FORM ACTION="[URL]" METHOD=GET>
<INPUT TYPE=submit VALUE="Text on button">
</FORM>

If you want to line up buttons next to each other, you will have to put them in a one-row table, with each button in a separate cell.
Note that search engines might not find the target document unless there is a normal link somewhere else on the page.
A go-to-other-page button can also be coded in JavaScript, but the above is standard HTML and works for more readers.

<a target="_blank" href=...> opens a new, unnamed window.
<a target="example" href=...> opens a new window named "example", provided that a window or frame by that name does not already exist.
Note that the TARGET attribute is not part of HTML 4 Strict. In HTML 4 Strict, new windows can be created only with JavaScript. links that open new windows can be annoying to your readers if there is not a good reason for them.

First, label the destination of the link. The old way to label the destination of the link was with an anchor using the NAME attribute. For example:
<h2><a name="section2">Section 2: Beyond Introductions</a></h2>

The modern way to label the destination of the link is with an ID attribute. For example:
<h2 id="section2">Section 2: Beyond Introductions</h2>

Second, link to the labeled destination. The URL is the URL of the document, with "#" and the value of the NAME or ID attribute appended. Continuing the above examples, elsewhere in the same document you could use:
<a href="#section2">go to Section 2</a>

Similarly, in another document you could use:
<a href="thesis.html#section2">go to Section 2 of my thesis</a>

The URL structure defines a hierarchy similar to a filesystem's hierarchy of subdirectories or folders. The segments of a URL are separated by slash characters ("/"). When navigating the URL hierarchy, the final segment of the URL (i.e., everything after the final slash) is similar to a file in a filesystem. The other segments of the URL are similar to the subdirectories and folders in a filesystem.
When resolving relative URLs (see the answer to the previous question), the browser's first step is to strip everything after the last slash in the URL of the current document. If the current document's URL ends with a slash, then the final segment (the "file") of the URL is null. If you remove the final slash, then the final segment of the URL is no longer null; it is whatever follows the final remaining slash in the URL. Removing the slash changes the URL; the modified URL refers to a different document and relative URLs will resolve differently.
For example, the final segment of the URL http://www.mysite.com/faq/html/ is empty; there is nothing after the final slash. In this document, the relative URL all.html resolves to http://www.mysite.com/faq/html/all.html (an existing document). If the final slash is omitted, then the final segment of the modified URL http://www.mysite.com/faq/html is "html". In this (nonexistent) document, the relative URL all.html would resolve to http://www.mysite.com/faq/all.html (another nonexistent document).
When they receive a request that is missing its final slash, web servers cannot ignore the missing slash and just send the document anyway. Doing so would break any relative URLs in the document. Normally, servers are configured to send a redirection message when they receive such a request. In response to the redirection message, the browser requests the correct URL, and then the server sends the requested document. (By the way, the browser does not and cannot correct the URL on its own; only the server can determine whether the URL is missing its final slash.)
This error-correction process means that URLs without their final slash will still work. However, this process wastes time and network resources. If you include the final slash when it is appropriate, then browsers won't need to send a second request to the server.
The exception is when you refer to a URL with just a hostname (e.g., http://www.mysite.com). In this case, the browser will assume that you want the main index ("/") from the server, and you do not have to include the final slash. However, many regard it as good style to include it anyway.

The title displayed is the title of the frameset document rather than the titles of any of the pages within frames. To change the title displayed, link to a new frameset document using TARGET="_top" (replacing the entire frameset).

These things are necessary for Web-based uploads:

► An HTTP server that accepts uploads.
► Access to the /cgi-bin/ to put the receiving script. Prewritten CGI file-upload scripts are available.
► A form implemented something like this:

<form method="post" enctype="multipart/form-data" action="fup.cgi">
File to upload: <input type=file name=upfile><br>
Notes about the file: <input type=text name=note><br>
<input type=submit value=Press> to upload the file!
</form>

Not all browsers support form-based file upload, so try to give alternatives where possible.

The Perl CGI.pm module supports file upload. The most recent versions of the cgi-lib.pl library also support file upload. Also, if you need to do file upload in conjunction with form-to-email, the Perl package MIME::Lite handles email attachments.

The only reliable mechanism for processing form submissions is with a server-side (e.g., CGI) program. To send form data to yourself via email, you should use a server-side program that processes the form submission and sends the data to your email address.
Some web service providers make standard form-to-email programs available to their customers. Check with your service provider for details.
If you can install CGI programs on your own server, see the answer to the previous question for a list of useful resources.
If you can't run CGI programs on your own server, you can use a remotely hosted form-to-email services. Note that the provider of a remotely hosted service will have access to any data submitted via the service.
Forms that use action="mailto:..." are unreliable. According to the HTML specifications, form behavior is explicitly undefined for mailto URIs (or anything else other than HTTP URIs). They may work one way with one software configuration, may work other ways in other software configurations, and may fail completely in other software configurations.

This feature is a byproduct of frames (In many opinions, the only good things frames did for web design). On any HTML page, you can just add target="_blank" to your link syntax. e.g. yoursite.com