File Formats

File Formats

Web pages can contain different multimedia elements: text, graphics, sounds, video, and animation. To identify the format or type of file, an extension (a usually three-letter suffix) is usually added to the file name when it is saved on disk.

Text The most common extensions for text files
are .txt, .pdf, .doc, and .htm (or .html).
Most of the text files that you find on the
Web have the extension .htm, created with
the hypertext markup language.

Graphics Graphics on the Web can include pictures,
photos, paintings, image-maps, and
buttons. The most common extensions are
.gif (for a standard image format developed
by CompuServe) and .jpg or .jpeg (created
by Joint Photographic Experts Group).

Sounds The Internet is a great place to find and
hear songs, movie soundtracks, and
recorded interviews. The most common
formats are these:
• .wav: Wave files can be played with
Sound Recorder included in Windows.
• .ra or .ram: RealAudio files can be
heard with RealPlayer, a plug-in you
can download from the Web.
• .mp3: Compressed music files that can
be played with an MP3 player.


Video and Animation You can see cartoons and movie clips on
the Web, but you need the appropriate software. Videos are usually stored in files
with .avi, .mov, and .mpg (or .mpeg)
extensions. To view MPEG videos, you
just need Video for Windows. However, to
create high-quality movie clips, you need a
special MPEG expansion card. You can
also find animation and 3-D worlds. One of
the standard tools to manipulate animated
worlds is Java.

Compressed Files When you download files, they may be
compressed. Windows compressed files
usually have a .zip extension.