Why do we need storage?
What do we need to store?
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This chapter is concerned with the role of memory in the modern computer.
Get hold of a shared web page unique to your class. EG set up at [] (account needed). On that page, produce a list of things related to school that you need to store. - Extension: Categorize your list into how you store things.
In class, share and discuss your lists
Description of store from the ICT (user) point of view.
On most computers you would need to:
- Click on 'File' in the Menu
- Find and click on 'Save File As'
- Choose and select a folder to save the page into
- Choose and select how to save the page (choose Web Page Complete)
When you have done that - go and look in the folder to see what has been saved. Is it one file or many? How much space has been used?
Finding Out ActivityEdit
If we agree that a computer can store all sorts of things - how does it do it? This was the problem that faced the first pioneers of computing. By chance someone observed that Looms, from the fabric industry, were controlled using data storage on cards with holes punched in them. This allowed the pattern to be loaded into a loom line by line as the material was produced. Babbage's design used punched cards to set mechanical switches to store a series of instructions and numbers, allowing his design to perform a basic set of maths (add, subtract, etc.).
His second machine, the Analytical Engine used 1000 banks of levers able to store a 40 digit number each and filled a room. This huge machine could store less information than would be needed to display the text in this chapter of this book.... but the problem of scale was soon to change.
The following is a list of tried and tested classroom activities.
Be A computer!
The LMC app shows how a computer uses the fetch - decode - execute cycle to pull instructions and data from memory.
Your teacher will let you know how to hand in this task.
Electronic Store of DataEdit
Electronics has revolutionised the mass storage of data, as the switches used are so small - in some cases just a few atoms in size. The rate of progress of miniaturisation is known as Moore's law But how are switches used to store data, e.g. a picture - how does that happen? Read the chapter on Data Representation to find out.