Chapter2 Flashcards
What are the functions of the computers?
1) processing (CPU)
2) storage (HD, USB, CD, DVD, Blueray, SSD, SD-Card)
3) Output devices (Printer, Speaker, Monitor, Projector, Headphones, TV Screen, Projector, Tactile devices, Braille display ”send data out of the computer”)
4) communication devices (Modem, Network card, Bluetooth, WI-FI Card)
5) input devices (keyboard, graphics tablet, microphone, webcam, touchscreen, scanner, mouse, ocr reader “enters data & instructions”)
How can you convert from decimal to binary?
Keep dividing the number by two removing any fraction on the odd numbers plate a 1 and the even numbers place a 0 until you reach 1 this will be your binary number writing it from down to up starting from the 1
How can you convert from binary to decimal?
You get the number and put it on the 8 weight scale and see its value in the 2^N (1,2,4,8,16,32,64,128)and add there totals
How do you represent texts?
1) using ASCII characters (each character has 8-bit code, 256 unique codes for 26 letters, 10 digits, special characters)
2) Unicode (supports more than 100,000 unique characters, uses 32 bits, includes Chinese, Arabic, Japanese characters)
What is meant by digitization?
Representation of audio, video, & photos using binary system devices used in such a thing are called analogue-to-digital convertors (ADC)
What is the binary system?
The system used to store, process & exchange data in computers, having two symbols 1 & 0
What is a Bit?
A binary digit, Its the smallest unit of information a computer can process of value 0 or 1
Why is the binary system used in computers?
It is more suitable as it is easy to store by the use of electricity, easy to process having operations of 2 values, easy to read as there is only two values, it is a easy way to represent numbers, text, instructions, photos, videos, etc
1 byte is equal to how many bits?
8
How many values a byte can represent?
256
2^N
A kilobyte is how many bytes?
1KB = 1000 Bytes
A megabyte is how many bytes?
1MB = 1million bytes = 1000KB
A GIGABYTE is how many bytes?
1GB = 1000 MB = 1 Billion bytes
A Tera byte is how many bytes?
1TB = 1000GB = 1 TRILLION BYTES
A Petabyte is how many bytes?
1PB = 1000 TB = 1 Quadrillion bytes
How is data transfer measure?
In bits
What are the computer components?
1) microprocessors, CPU (central processing unit)
2) storage (RAM/ROM)
3) connectivity
What is meant by green computing?
It is the use of computers and related resources in an environmentally responsible manner, you can:
1) use e-Resources instead of printing
2) use energy saving devices
3) recycle electronic waste
4) turn off the devices when not in use
What are the future trends in computers?
1) Robot servant
2) commuter robot
3) Iot smart cities
4) virtual screens
5) OLED Display (transparent screen)
6) flying cars
7) bendable smartphones
What is a CPU?
Central processing unit, an electronic chip that carries out the instructions of computer programming located on the mother board performing:
1) Arithmetical (+, *) 7 logical operations (<, =) “ALU”
2) Input/Output operations of the system (control)
It has several performances:
1) clock speed, measure in Hertz where 1 GHz = 1 billion clock cycles per second
2) world size with its natural unit being 32bits in older pc, 664bits in new pc, embedded systems uses 8 & 16 bits
There is single core cpu, multi core cpu which is multiple cpu on a single chip performing parallel processing, contains cache memory which is an internal storage of data in CPU
CPU must have certain compatibilities:
1) Software compatibilities (all softwares must be compatible with every CPU)
2) backward compatibility (newer cpu versions should be able to run apps designed for older versions)
What are the types of memory in a computer?
1) Random access memory (RAM)
2) Read only memory (ROM)
3) flash memory
4) Hard drives (permanent storage)
5) cloud storage
What is a random access memory (RAM)?
1) Primary to rate of memory
2) temporary storage for programs and data
It has certain features:
1) Unique address
2) data can be stored and retrieved randomly
3) very fast access (in nanoseconds)
4) data is erased if the power goes off (volatile)
What is read only memory (ROM)?
1) it contains:
1) startup information (booting)
2) critical data
Features:
1) cannot write new information
2) cannot be erased (etched on the computer)
What can a flash memory do?
It can read/write/erase data, it is non-volatile (data don’t get erased when the power is switched off)
What is a hard drive?
It is a primary device used for permanent storage, it is a secondary storage, store programs & data, it is slower than main memory, huge storage capacity there is two types: 1) internal 2) portable
What is the memory speed and storage capacity of the different storage devices?
Fastest is CPU (Hz), L1 cache (KB), L2 cache (KB, MB), L3 cache (MB), RAM (GB), HDD (GB, TB) and their storage capacity is from the last to first.
What are the types of cloud storages?
1) Dropbox
2) OneDrive
3) iCloud
4) Google Drive
What are the features of cloud storages?
1) easy access (you can access it anywhere as long as you have internet connection)
2) huge storage capacities
3) online backup
