Decoding the new programmes of study for computing
Data and data representation
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3.Data and data representationMuch of the power of computers comes from their ability to store and manipulate very large quantities of data very quickly. The way in which this data is stored and manipulated can make enormous differences to the speed, robustness, and security of a computer system. Not much of this section is directly relevant to the KS1/2 POS, but I hope that you may nevertheless find it useful. 3.1BitsData in a computer is (almost) invariably represented as bits (short for “binary digit”). A bit is either a 1 or a 0. It’s easy to see how bits can represent a black and white picture. For example, here is a crude picture of a table, represented as a 5x4 grid of “pixels”. If we display 1’s as black and 0’s as white, we get a picture.
If we devoted two bits to each pixel we could represent shades of grey, like this:
Now we can draw a table with light grey legs and dark grey feet:
If I want more shades of grey, I can use more bits for each pixel. Two bits can represent four shades, three bits can represent eight:
Four bits can represent 16, and so on. The number of shades we can represent doubles each time we add one more bit. We can represent colour pictures too, of course, using three groups of bits for each pixel, one for the degree of redness, one for blueness, and one for greenness. 3.2Bits for everythingBits can represent things other than pictures.
In short, bits can stand for, or represent, absolutely anything. When you stop to think about it, that’s quite remarkable. Bits are a kind of universal medium for representing information. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 142.38 Kb. Share with your friends:
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