You can create or copy and store a wide variety of files on your computer.

Each file consists of two parts:

• a filename assigned by the creator of the file
• a filename extension that designated the type of file and the software used to create and access that file

The standard format for a file is filename.ext where filename is the description you give to the file and ext is the 3 letter abbreviation for the type of file.

For example, the name of the file you are currently reading is filetypes.htm

Different kinds of software create different kinds of files:

• Microsoft Word creates files with the doc (for document) extension
• Microsoft Excel creates spreadsheet files with the xcl extension
• Microsoft Word can also create text files (filename.txt) which can be read by any word processing program
• Most word processing programs can also save a file in rich text format (filename.rtf) which retains the original formatting of a file but allows it to be read by any word processing program.
• Adobe Acrobat creates .pdf (public domain format) files which can be read with the free Adobe Acrobat Reader

In creating web sites you wll be working primarily with two kinds of files:

• page files which will have either an htm or an html (for hyper text markup language)extension
• graphics files wich will have either a gif or a jpg extension, depending on the format of the graphic

When you create and name a file, follow a few simple rules:

• try to use short (8 or fewer letters) descriptive filenames
• use lower case letters only
• do not use spaces in filenames (if you must use a space, indicate it with the underline key, e.g., my_space.htm)