We always can see some files in this kind of format anywhere on PC. What is it? Did somebody know what softwares can be used to change a file into that format?

The .dat extension is just the name given to the file type by the programmer. In this case it's probably just a generic data file for the application it works with. Most of these files are binary, meaning they can't be read by a human, so don't worry about them.

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Then how the programmers read the data, how they change the files into .dat format and how its application reads them.

If I understand you correctly, you're asking how does the programmer know what's in the .dat file and how does the program use it?

The programmer just decides that the information required by the program is stored in a file that he marks w/ a .dat extension. He could have given it another extension but it really doesn't matter as long as the program knows where to find the files. The information stored may or may not be binary; it could just be a text file given the .dat extension. If you're really curious, just try opening the file in a text editor and see what it looks like. If it has a bunch of funny symbols, then it's just binary data.

For example, say I wrote a program to store phone numbers. When a user input a phone number, the program saves the phone number into a file called phone.dat. The program knows all phone numbers it has saved have the .dat extension so when the user asks to program to look up a phone number, the program will look through the list of .dat files for the one that matches the request.

You can change any file into another type simply by changing the extension (at least in Windows). If you have a .html file, you can change the extension to .txt so that your web browser no longer opens it by default. The information hasn't changed, just the application that will open it.

Hope this answers your question.

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Yes, I was asking that. Thanks a lot for your reply. Is the program change the .dat file into another format before it(means the .dat file) is opened?

Not sure what your asking exactly. If your asking from a programmer's perspective, then it depends on how the programmer designed the program.

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Is my English bad? Then why are you didn't understand my question? What I asked was how does the program read the .dat file? No a program is able to support the .dat file, right? If it's that, is a program change .dat file into another format first before the .dat file can be opened and read?

Obviously it's a problem with crystalattice's English

A .dat file is a data file associated with a program that uses the file. There is no specific format. It is not convertable into another format. It is simply a file that contains data that a program opens, reads, uses. No magic, no weird conversions. The format is defined by the program itself because the program reads the file in a specified way known only to the program itself.

You cannot convert it into another format.

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Here's the thing: Anyone can write a program that creates and uses a file named "something.dat", and there is no such thing as the .dat file format.

Instead of giving a hard time to people who are trying to help, I have a suggestion: do some additional investigation on your own. I think that gidforums is one of the absolute best places to begin when you have a question, and I hope that no one discourages you from coming here.

However --- you have a web browser and there are many search engines that can be used to look for information. Even if you find an answer that seems satisfactory, my recommendation is never to depend on information from one source.

Poke around and try to find other points of view. Maybe they are all at least partially correct but no single one has the complete "answer". Also, sometimes things you see and read on the web (or anywhere else) are just flat wrong. (Gasp!) See footnote.

As an example of what's out there, here is a reference that shows that there are a very large number of known applications that create and use files with the name "something.dat".

http://filext.com/detaillist.php?extdetail=dat

To quote from that site: "A search on the file extension you submitted shows 37 record(s)."

In other words they list 37 different programs that use files named "something.dat". (And they all have different kinds of data in different formats.) I have a couple of applications on my system that use .dat files and those aren't even in the list. (Library index files for ModelSim VHDL simulators is one example.)

They also say, "Can be just about anything: text, graphic, or general binary data. There is no specific structure for a .DAT file. You can use an editor like EditPad Pro to look inside a .DAT file and possible determine its contents and relationship with a program."

So the reason that no one has answered your question is that there is no answer. Every word in your question was a perfectly good English word and the words were strung together with gramatically correct syntax and in a way that is understandable. The problem is that you are assuming that there is an answer, since you are apparently assuming that all .dat files have the same format and store the same kind of information in that well-defined structured format.

Tain't so, McGee.
(Quote from 20th century radio comedy series "Fibber McGee and Molly", meaning "That is not a true statement." Originally from a song title "Tain't so, Honey, Tain't so" --- I think.)

Regards,

Dave



Footnote.

Bottom line: It's always OK to ask, but don't get all of your information from one source. The amount of information available to us in these early years of the 21st century is truly astounding. All with the press of a key (or two) or a click (or two) of a mouse.

On the other hand...

Someone once told me that 85% of the stuff on the web is "crap". I replied that in my opinion, "85% of everything is 'crap', so what's your point?" Don't just gather and absorb "information": analyze and criticise; that's the ticket!

---davekw7x

Hence, my confusion as to what answer you're looking for. There is no set answer for what you're asking; how a .dat file is used depends strictly on the program in question and what the programmer decided to do with the files it uses.

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Common Sense v2.0-Striving to make the world a little bit smarter.