Searching the Web

Volume 30, Number 4, April 2003

Searching by File Type

Holly Gunn

The file extension of a computer file indicates the format of the file. A PowerPoint file has the extension .ppt; an Adobe Acrobat file has the extension .pdf; a Word document has the extension .doc. There are many more file extensions.

Some search engines are capable of searching by certain file types. Google can locate pages saved in a number of file formats, including Adobe PDF, Powerpoint and Excel. AlltheWeb can also locate Adobe PDF files. This is particularly useful if you are looking for reports in PDF format or PowerPoint presentations about a particular topic.

You need to know four things to search by file type:

1. Which search engines have this capability;
2. The file formats these search engines are able to locate;
3. The file extensions for particular file formats; and
4. The search syntax needed in each search engine to search by file type.

Try these file type searches with Google

intitle:“school library” filetype:ppt
This search retrieves a PowerPoint presentation with the phrase “school library” in the title.

intitle:“school libraries” filetype:pdf
This search retrieves PDF documents with the phrase “school libraries” in the title. Frequently organizations put lengthy reports or policy documents on the Web in pdf format so searching by this file type can retrieve useful documents.

Try this file type search with AlltheWeb Advanced.

In the Word filters section, type:
-“school library” in the title
-"planning" in the text
In the Results restrictions section, check "Adobe PDF" in File Format

Google Advanced and AlltheWeb Advanced enable searching by file type as a menu selection, making the memorization of search commands for searching by file type unnecessary.

To learn more about file extensions, explore these helpful sites and online tutorials:

File Extensions Dictionary

Search File Extensions

File Extensions and How They Work: Tutorial

Holly Gunn is the teacher-librarian at Sackville High School, Nova Scotia. She can be reached at hgunn@accesscable.net.