Google Tips: Search within documents of a specific file type (PDF, DOC, XLS, TXT, HTM etc)

What many do not know: Google can also be used to search the Internet for files of a certain type containing a given content.

For example, with this, you can search for a PDF document (PDF), a Microsoft Word document (DOC), an Excel spreadsheet (XLS) or a text file (TXT) containing any search term. The only thing you have to make sure is to attach "filetype:" with the appropriate file extension to your search query.

Here are some examples for DOC, XLS, TXT and HTM documents:

word filetype:doc
"word1 word2" filetype:xls
word filetype:txt
word filetype:htm

The imagination knows no bounds with this, it can be searched in any desired file extension, which may contain a text. So, it is not possible, for example, to search audio files and video files.

Code Search

Among other things, this issue is very interesting for programmers who are looking for a particular code. Thus for example, with the request "unicode filetype:pas" you can search for Delphi or Pascal code that contains the word "Unicode". Of course, the search term can then occur both within the code or within a comment of the file and it is amazing how much code Google provides.

So, if you are not sure about a particular construct, you can easily google it and limit the search to your programming language by using the file extension and you are usually finding something.