1. difference between data and information

Have a look at this link. This is how a flight reservation slip usually looks like. But you can't really extract a lot of information from such a paper. These are only some coded data from a computer. What happens when you change this reservation slip for a real flight ticket? The agent in the office will input the code of reservation into the computer (in this case L5M684) and the output will be a table like this. Can you find out more information now?
As you see the data from the computer changed into an understandable information for a person. The same happens the other way around - information that people can understand is typed into the computer and it changes into data.

2. data coding into a computer

Computers can't think. In order for a computer to understand the data, there has to be some coding system that the machine could read and understand and perform accordingly. The only way a computer can communicate is through the electrical impulses. Inside the computer you would finde thousands of miniature switches that can be only in two positions - on or off, 1 or 0. Each switch represents 1 bit. That means that the only way a computer can communicate is through a coded language of 1s and 0s - in a binary code. And the data the computer works with or stores are coded in this language.
To summarize it - information is the facts that we read on the monitor or that we input into the computer; data is a string of 1s and 0s that can be saved onto a medium (like a disc, CD etc.) and with which the computer can perform calculations.
We will now have a closer look at how texts, images and sound is coded into the computer.

3. coding the text

As you probably know or figured out by yourself, each character has its own code under which the computer distinguishes it. There are several standards for character coding - the best known are ASCII (uses 7 bits for each character which means it has 128 different characters - this is not sufficient for most languages), Unicode (uses 16 bits which means it has 65 536 different characters) and Windows 1250 (uses 8 bits which meands 256 characters).

Task for you: using the Windows 1250 table change the word "World" into a binary code the computer would understand. Do the same the other way around - decode this string: "01001101 01111001 01110000 00100000 00110101".

4. coding the images

Lets have a look at the bitmap graphics first. If you look at the images in your computer very closely you find out that they are composed of tiny dots - pixels. In a black and white picture each pixel is represented by a 1 or a 0. If the picture is colored, each pixel is coded with more bits that carry also the information aboul the color - if a coloring of 16 colors is used each pixel will have 4 bits, if 256 colors were used each pixel will have to be coded by 8 bits. 65536 colors or High Color means 16 bits for pixel and 16 milion colors or True Color means 24 bits for a pixel.

Task for you: code this picture into a string of 1s and 0s. Do the same the other way around - decode this string:
00111100 01111110 11011011 11111111
10111101 11000011 01100110 00111100

Open now MS Paint and Inkscape and try to paint simple geometric shapes in both of them. Do you see the difference? Inkscape is a vector editor and the graphic we create by using it is called vector graphics. The shapes are independent objects and they are also saved as independent objects. A code for their saving is in fact a guidance for their recreation. For example a code of an yellow circle of radius of 40 pixels with co-ordinates of [200 150] would probably be something like "C40Y200 150".

With movies it is similar as with bitmap graphics, just a lot more compression needs to be done.

5. coding the sound

We know three basic file types in coding the music.
Wav is the most exact file type - there is no compression done. The sound captured by a microphone is translated into a digital signal by a sound card and a software for sound recording creates a Wav file. When you want to replay this file, the coded information goes as a digital signal to a sound card and is translated back into an analog wave that we can hear.
MP3 is a compressed Wav file. They are much smaller than Wav. The compression has been made by cutting away those frequences which a human ear can't possibly hear.
Midi is a simple coding system which uses similar guide for playing as the vector graphics uses for drawing. Only simple melodies played with computer generated musical instruments are fit for Midi format - it is not suitable for human speach or realistic sounds.