Revision Flash Cards

Question	Answer
Describe a basic computer system.	Image: Computer_System.PNG (image/PNG)
What is the role of the CPU?	To fetch, decode and execute commands.
What is the base number of binary logic?	8
What is 0001 1101 in denary?	29
What is the base number in hexadecimal?	16
What is 5C in denary?	92
What does ASCII stand for?	American Standard Code for Information Interchange.
What uses ASCII?	PCs
What is the base number of ASCII?	7
How does ASCII represent text in a computer system?	Each character is given a code that is stored in binary. 1 byte = 1 character Characters coded include letters, digits, punctuation and control characters such as tab and enter.
What is the difference between ASCII and Unicode?	ASCII uses either 7 or 8 bits to store code; this means it can store a maximum of 256 characters. Unicode uses 16 bits to store characters and so can store many more characters (65,536).
What is an Input Device?	A device that can be used to insert data into a computer system.
What is an Output Device?	A device connected to a computer that takes information from the computer and gives it out as an analogue signal - as an image, sound, etc.
What is RAM?	Random Access Memory that temporarily stores data. This form of storage is volatile that means when the power is switched off, the data is not saved.
What is ROM?	Read Only Memory. This is memory that cannot be changed is is non-volatile. It contains the boot-up code that is needed for when the computer restarts.

Resource summary

	Created by Tom Mitchell about 10 years ago