File type, file format, search, search engines, search by file,

Searching by file format

There are a number of different file formats that searchers can use. Each will provide access to different types of information.

Adobe Acrobat or .pdf Data that is often found in this format is 'official' information - perhaps a company brochure or annual report, a university prospectus, or a government white paper or discussion document. It's usually used if an organisation wants to have their information displayed in exactly the same format electronically as in the paper version. As a result, if you need authoritative, official documents, facts, comments and so on, this is a good way to restrict the search.

PowerPoint files or .ppt A lot of people will use PowerPoint presentations if they are training for example. It's an easy and useful way to provide basic information for delegates. It's also a way for a searcher to locate training materials, tutorial data and so on. Great if you have to run your own course and are looking for inspiration, or need an overview of a subject.
A lot of speakers at conferences will present their research or speeches in a PowerPoint format, and this is often made available online after the conference. Therefore, if you need to locate experts in an area, potential speakers, or just need to keep up to date with developments in a particular subject area, limiting your search to this format may well help you find what you need more quickly.

Autodesk or dwf format is a secure file format developed by Autodesk 3D Design for the efficient distribution and communication of rich design data to anyone who needs to view, review, or print design files. The sole purpose of DWF is to allow designers, engineers, project managers, and their colleagues to communicate design information and design content to anyone needing to view, review, or print design information.

Excel Spreadsheets or xls Spreadsheets are often used for providing access to statistical or financial information. Need to find the population of an area? GNP figures? Forget wading through pages of HTML; go straight to a search engine and limit your results to the xls format!

Adobe PostScript files or ps This is the worldwide standard for printing visually rich documents. If you need data in a rich graphics format limiting a search to this file type could be worth trying.

Rich Text Format or rtf This format allows you to take data in an rtf format and import it into different applications or operating systems such as between a pc and a mac. Useful if you need data that you can then play around with and manipulate in a variety of different ways (as long as you have permission, of course!).

Word or doc Files in this format will often contain a great deal of useful information in more depth and detail than you'll find on a web page. Download the file, open it in Word or any other compatable word processor and print for easier reading.

Corel WordPerfect or wpd files If for some reason you don't use Word, limit your search to this format to easily import the data into that package. Saves time reformatting!

Google Earth kml or kmz format. KML is a file format used to display geographic data in an Earth browser such as Google Earth, Google Maps, and Google Maps for mobile.KMZ stands for KML-Zipped. It is the default format for KML because it is a compressed version of the file. One of the more powerful features of KMZ is that it allows any images you use - say custom icons, or images in your descriptions - to be zipped up within the KMZ file.

Shockwave flash format or swf is a file format for multimedia, vector graphics and actionscript in the Adobe Flash environment.

Other file formats

There are plenty of other file formats available for people to use, but few of them work with search engines. However, if you want a good overview of file types, or you've got a filetype and you want to know what it means, try:

Fileformat has a search option and an A-Z directory.
FileInfo contains a searchable database of thousands of file extensions with detailed information about the associated file types.
Filext lists over 50,000 filetypes.

Search engines to use

Exalead Advanced for .txt .pdf .doc .xls .ppt .rtf .wpd .swf Annoyingly, Exalead don't tell us exactly which file types they make use of, so there may be other options available that I don't know of. The format is term filetype: txt which is to say a space after filetype: with no fullstop before the extension name.

Google Advanced search for all of the file types mentioned above. The format is term filetype:txt which is to say without a space after the filetype:

Yahoo Advanced search for .htm .pdf .xls .ppt .doc .txt The format is term filetype:txt OR filetype: txt which is to say you can go with a space or not.

Bing is not helpful. It does filetype search in the format of term filetype:txt but doesn't tell us which types it actually supports. I am guessing .html .pdf .txt .doc .rtf .xls .ppt

There are other search engines that will search for specific types of file for you however.

Findthatfile Common searches are for PDFs, Documents, Audio, Video, RAR and ZIP compressed files, Fonts.
Great PDF Search Engine. is a pdf search engine for PDF ebooks, manual, catalogs, sheets, forms and documents.
PdfPick PDF Search Engine. Very basic.
PDFSearchengine Searches for PDF, CHM, DOC, RTF and TXT files.
Pdfsearchengines for ebooks, documents, PPT and Excel files.
SlideFinder A Search engine for PowerPoint presentations.
soPDF searches over 435 million PDF files.
Fagan Finder Search by file format has the option of searching for 17 different file formats from 7 search engines. However, this is now quite elderly, so may not be entirely accurate, but it's still worth a try.

If you have never tried limiting by file type, think laterally and give it a go. You may well find that your results are smaller, more accurate and better focussed!