As you accumulate a large number of Web documents, you will likely begin organizing
different Web applications within separate directories subordinate to your root directory -- your main Web
directory. The figure below illustrates this idea with three subdirectories within root
directory Website, each containing Web pages. Application3
folder, in addition, contains a Media folder for storing all graphic files
pertaining to that application.
When coding the src attribute in an
<img/> tag or the href
attribute in an <a href> tag, you need to trace the
directory hierarchy from the Web page containing the tag to the location of the
actual image or page specified in the link. This means that you may need to go down one or more
levels of directories to find the picture or linked page, or that you need to go up the
hierarchy to find the picture or page, or that you need to go up the hierarchy into a
higher-level directory and then down into the folder containing the image or link.
The reason for this up and down traversing of directories is because linked pages or images are
referenced relative to the page containing the link. For sake of argument, in the above
illustration suppose that pageA.htm in directory
Application1 contains an <img/> tag pointing to
picture1.gif in the Media subdirectory of directory
Application 3. In order to make the src reference from
pageA.htm to picture1.gif the following path is
Go up one level from the Application1 folder to the WebSite folder.
Go down one level from the WebSite folder to the Application3 folder.
Go down one more level from the Application3 folder to the Media folder.
Two types of path specifications are used to traverse a directory hierarchy to locate Web pages and
Code two dots followed by a forward slash ("../") for each level traversed
up the folder hierarchy.
Code a folder name followed by a forward slash ("/") for each level traversed
down the folder hierarchy;
Therefore, the URL for an <img src=""/> link from page1.htm to
picture1.gif would be
From the current directory containing page1.htm, back up one level
(../) from the Application1 directory to the
WebSite directory. From the WebSite directory,
go down through the Application3/ and Media/
directories to find picture1.gif.
Normally, path specifications are not as complex as this. It is common for a folder containing
Web pages to collect all images used on those page in a single Media subfolder
inside the Web page folder. Then, a src link to an image would only need
to point down one level of directories:
The above examples connect from a Web page to an image. The same process is followed when linking
from one page to another. In the above directory structure a link appearing on
pageA.htm to page2.htm would be
<a href="../Application3/page2.htm">To to page2.htm</a>
It is fairly simple to trace the path from a Web page to a graphic image or other Web page
if you focus on the folder structure, starting with the folder containing the page and ending at the
folder containing the file. Also, remember to pay attention to the directory tree; you must follow the
hierarchy up and down the branches of the tree rather than making lateral references where no
lines connect the folders.