Hello again,
This time in our post we will talk about digital organization and digital representation and we also going to mention some things about Metadata and Marking-Up.
101000101010001... No I am not mistaken that is what I wanted to write, but what exactly is this? What it represents?
The most important is who or what will "interpret" it. For a human being this could be a number but for computer systems this could possibly represent something different.
Humans count and generally perform arithmetic by using the base ten number system, which is the most known number system. But except from this system there are also and many others with different bases, and to make it more clear when we mention base we mean the number of different digits that are being used to represent data. In each of these systems we combine the digits in a way that means something to us.
Similar is the way that computer systems work. The computer systems are based on the binary number system, which is consisted of only two digits, zero ("0") and one ("1"). With this specific number system the computer systems organise and represent information/data. Inside the systems a binary digit is represented with an electromagnetic state. Zero means non-positive electromagnetic state and one means positive electromagnetic state. So all the data that
are being stored in computer systems are being stored as binary code (sequences of binary digits) and because of this we often refer to them as digital data.
Each zero and one is known as bit, as sequences of 0 and 1 the computer systems can store in optical or hard disks large amounts of data. A sequence of 8 bits is known as byte (the most known unit of digital information). Every sequence of bits represents something different but something that is very interesting is that if we increase by one bit the sequence of bits then we can represent twice as many values as all the previous sequences can.
As we said the binary system is used to represent, organize, store and send data and when we say data we don't mean only numeric but also alphabetic (text) and alphanumeric data that have a specific purpose. Those data in their binary form are being interpreted from processors, according to appropriate agreed methods of interpretation (file formats), to create characters that are easier for humans to read. The most characteristic examples of character encoding schemes are the ASCII and the Unicode.
All these data is obvious that need to be organised in an efficient way. That's why is being used the concept of the file. "A computer file is a block of arbitrary information, or resource for storing information, which is available to a computer program". The size of a file must be finite. The information that a file contains can consist of smaller pieces of information which can be individually different but will have some common things (certain topic, theme etc.). The advantage of files is that can be manipulated as a single entity and can be grouped into folders which are collections of related information. With the folders we have a hierarchical organization of the files, because each folder can contain sub-folders. In this hierarchy the initial folder that contains all the other sub-folders is called "root". So beginning from the root we can follow a "path" through the sub-folders in order to find the file/s that we are interested in.
We mentioned that through the different file formats that exist we can store in files and textual information. But this information is just simple text without any evidence of how this text that the files contain is going to be displayed, where do we need to emphasize and where we need to use other fonts, generally there isn't any information about how the text should be presented and the semantics of it.
That's where the metadata and the marking-up are very useful. The metadata is data about data, in our case is more information about how the textual context of the file should be interpreted. On the other hand marking-up is the "action" with which we can add metadata on the contents of text files. The marking-up can be done in two different ways, the presentational and the semantic. The former has to do with how the text should be presented and the latter with what the text means. The semantic is the most important of the two because with this marking-up we can understand and process the data in a more efficient way.
So we can understand that is very important if we want to have all these data interpreted we need to know not only the format that those files have but also and the meaning of the marking-up that escorts them.
Summarizing we must say that the digital representation of data was a revolution to the representation of information. As a result now we are able to access as many times as we want any data without being afraid that would be compromised. Also we can easy create as many genuine copies of specific data as we want, transfer them to other computer systems and then by using processors interpret them again. Moreover, because of the digital representation of the data we can use the capabilities of the computers and manage great amounts of information in a more efficient and quick way, having as result the extraction of even more information from the data.
Humans/scientists took advantage, in a good way, of the theory that data have the meaning that people give them and through that they succeeded great things in the "world" of data organization and representation.
REFERENCES
- Richard Butterworth,based on original work by Jason Dykes (2009), "Digital Information Technologies and Architectures", Lecture 2:Digital Reoresentation and Organisation, Meta-Data/Markup, City University
- http://en.wikipedia.org/wiki/Computer_file
- http://whatis.techtarget.com/
- http://en.wikipedia.org/wiki/Byte
