File Formats Chapter 9 Bit Literacy

File formats are often ignored by users Applications automatically save files in the application’s format All formats are made for a reason, efficiency, effectiveness – saving the information needed to recreate the document as saved Many formats are commercial, they add to the creating company’s bottom line by keeping customers locked into the company’s software

Picture file formats Covered in Managing Photos

Audio file formats Most popular format MP3 Compressed by cutting off the “high” and “low” parts of the original recording, under the assumption that most humans can’t hear them – not as good as the quality of a CD Good enough – small enough for fast downloads, but “lossy” Most CD rippers create MP3’s

Other audio formats WAV (Windows audio-visual file) AIFF (Audio Interchange File Format) (Apple) These are popular with professional musicians Better quality than MP3’s, “lossless” Not compressed, so large files (10 MB for one minute of stereo audio)

Digital Rights Management DRM - added to some formats Prevents files from being copied or from being played on unauthorized devices AAC (extension.m4p) has DRM from Apple now labeled.m4a, Lossless, released as open source in 2011 DRM Subject of much controversy

Text formats Even with composing , you are creating text in a format of your choosing When you write a message in a proprietary format like docx and send it as an attachment, the recipient has to double click the link, which downloads the file, opens Word, lets them read the message, then go back to the client

Without attachments Without attachment, just include the text in the body of the The recipient just reads the message and is done Much smaller amount of data transmitted if the message you are sending does not require Word’s formatting, just send it in the body. without attachments can be read on any device that reads , regardless of whether it has Word on it or not

Text formats: Word Word was intended in the 80’s to be a word processor – for PRINTING on paper That is shown by the layout of Word screens, rulers, tab stops, fonts, “desktop publishing” These days all that is most often not necessary! Keeping bits as bits instead of spots of ink on paper is more efficient, more environmentally friendly, faster, cheaper

Word has versions MS Word has gone through many versions and they are mostly not compatible with each other Having an older version of Word will not let you read the files created with a newer version Profit for Microsoft!

Better: ASCII Inside a computer, EVERYTHING is a number – that includes music, sound, and text. In the early days of computers, every manufacturer had their own code for characters (HP, IBM, Sperry, Digital) The users didn’t care as long as they pressed A on the keyboard and got A on the screen

As time passed More computers meant more data and more users People wanted to share or buy or sell data from colleagues The incompatibilities in the character codes made a problem Eventually everyone decided that a “standard code” was needed

ASCII Several codes were considered but ASCII won! American Standard Code for Information Interchange The beginnings of the Internet in the 70’s also gave impetus to the desire for a standard code so that clients didn’t have to know a dozen different codes just to read from different machines across the Net

ASCII So what? Why do I care? Mostly, you don’t. If you press A on the keyboard and get an A on the screen, what does the code matter? ASCII is efficient, known by almost every device, easy to transmit and receive Has codes for A-Z, a-z, 0-9, space, punctuation marks and a few control codes 256 different codes (1 character fits into 1 byte of data)

Time passes The world starts using computers and not just countries who use the “Roman” alphabet First response: learn English But eventually the realization came that a new code that was bigger was needed Around 2000 Unicode was released “Universal Code” Has over 64K different codes

Unicode Covers all human alphabets and has room for more! Includes ASCII as first 256 codes A Unicode character takes TWICE as much space (at least!) as an ASCII character (2 bytes) Now in development for 4 bytes! Becoming the default code for many applications

Unicode Note: Unicode is NOT a “translator program” What it does do is allow you (if you know a foreign language) to write the foreign words properly spelled with the correct characters They will get transmitted correctly The recipient still has to know how to read them, but at least the words will be correctly spelled

Creating ASCII files most client editors create ASCII if you do not set “Use HTML” Notepad creates ASCII MS Word can create it if you are careful to save as “.txt” format Other free editors out there “UltraEdit”, “Notepad++”

Compare Text file and Docx file Text will be smaller, read by more different devices, will not become obsolete Docx file will be larger with hidden information in it, proprietary and will be obsolete the next time Word is updated People have gotten ‘bitten’ from the hidden information in a Word document