Understanding File Types (Extension)

We’ve heard a lot of File in our day today life. File is liFe with some arrangement of letters 😛 .

What is a file and how it works ? What are different kind of files ? How to read the files and why do we need a file type ? All of these will be cleared at the end.

What is a file ?

A file is something that has data in it. You can say a collection of similar type of data. For example a file which contains text is a Text file, a file with numbers and calculations in it could be an Excel file, and more. So It is basically a place where the data is stored and transferred.

At the bottom layer a file or any computer data is converted and stored in a zero/one format (0/1) i.e. binary data. So for our easy understanding this data is visible to us in text,image,etc formats.

At the end of each file you can check the extension i.e. FileName.txt , Filename.jpeg, some files extension are hidden and could be visible in properties.

There are very large variety of files that are available and used by different kind of people in the computer world. The most common file types are listed below :

Text (.txt) File : This is the file which most of us use for writing in notepad, wordpad (Rich Text) Software to open these files : Notepad, Notepad++, Wordpad, MS Word.

JPEG, PNG, BMP : are all the image formats. All of these could be visible in any image viewer of mobile/desktop/laptop. (wiki) (Joint Picture Expert Group , Joint Photographic Expert Group, Portable Network Graphics, Bitmap, Graphical Interchange Format )

MP4, 3GP, FLV, AVI, WMV : These are the mostly used video formats in daily use. A lot of players VLC, KM Player, MX player, GOM player can open these kind of files.

EXE : Most important file type that is Executable. So In windows operating system , this file means a specific program will be installed in your computer or a specific task could be done with this file. So handle this file with care as it can contain viruses too and malware Softwares too. This file type will run only on windows operating system.

DMG : This file is like exe but for MAC OS. It can contain Softwares for MAC OS.

DOC, DOCX, XLS, XLSX, PPT : These are file formats for MS Office suits. Excel, Word, PowerPoint can open these kind of files. They contain text, images, presentation, charts, and spreadsheets. Other softwares like Libre Office, Google Docs, Open Office can also open these kind of files. These are Mostly used files.

APK: Android Application Package is a file format used for Android devices for installation of games and Applciation. These file could only run in Android Operating System. These contains a lot of code which will run after installing the Applciation.

IPA: These files are only for Iphone Operating system. These are used for installing Application and Games in iOS.

JAVA, XML, PHP, SWIFT, JSP, JS,: And many more are the coding file formats which are mostly used by programmers. These file types contains text mostly in English but not understandable by common people. (NotePadd++ & Sublime editor can open these files)

MP3, M4A, AAC, AMR, 3GA,WAV : These are audio file types used from a long ago. The most iconic player was Winamp of that time, was favourite of many in windows OS to play audio files. Audio recording files are mostly stored as aac and amr. These files could also be opened in VLC player.

PDF : Most used but mostly unknown (Portable Document Format) is famous for readable in every place no matter what is your Operating system and where you open it. Be it a browser, WORD, Mobile, anywhere its the same.

Why So many file types ?

For specific file we write different kind of data in it. So for reading that data we need a file viewer that can decode that 101010 format and read whats written in it. An image could also be opened in notepad but that data will not be in readable format This is how it looks :