How we open a ms word document file with php?

It depends on what you want to do. You can pass the request to the system (only works for specific systems) or you can perhaps find a library that will allow you to do it.

AFAIK, only text files can be opened without special manipulation in most programming languages. (Database access does not count.)

Thanks

you can open an ms word document with its coordinations,How?OK Look:
to make a coordination you must use this:
$opened_file=file("THE FILE PATH")
$old_array=array('[b]','[u]','[i]');
$new_array=array('<b>','<u>','<i>');
$string=str_replace($old_array,$new_array,$opened_file);
To open a file use this:

Puckdropper is right, none of these code samples will actually work, as MS Word uses a binary file format, and might even refuse to open a file that had been modified with random bbcode/html added on the end. If you try very basic examples it will work, however MS Word creates all sorts of problems in the background using Word 97-2003 files. .docx files will fail entirely because of the zip file format.

What you really need to do is use COM to tell MS Word itself to handle parsing the file. You can create a new COM object with $word = new COM("word.application"); which basically opens up a copy of MS Word on the server and gives you access to it from PHP.

Take a look at this blog post on opening microsoft word files in php and extracting text. Naturally you need a Windows based server in order to do this.