Bits and Bobs

Question 1

Why do we use Hexadecimal?

Answer 1

• Simpler to remember than binary
• Quicker to write
• Less room for error (fewer characters)
• Easy enough to covert

Question 2

Where do we see Hexadecimal?

Answer 2

On the firmware

Question 3

Where do we see Binary?

Answer 3

Hardware

Question 4

Where do we see Python?

Answer 4

Software

Question 5

What does ASCII Stand for?

Answer 5

American Standard Code for Information Interchange

Question 6

How many bits does ASCII use?

Answer 6

7 bits usually, to encode 128 characters

Question 7

Why isn’t 8-bit ASCII still not enough?

Answer 7

It can encode 256 characters, but not enough for characters in other languages

Question 8

How do bitmap images make up an image?

Answer 8

Each pixel (picture element) is given a binary value which is assigned to a colour

Question 9

What would happen if you increase the number of bits in a bitmap image?

Answer 9

The more bits, the more colour combinations and the better the image will look

Question 10

What is Bit/Colour Depth?

Answer 10

The number of colour combinations/amount of colours that can be seen

Question 11

How to calculate image size?

Answer 11

Colour Depth x Resolution (Width x Height)

Question 12

How many bits does UNICODE use?

Answer 12

16 bits, 136,755 characters

Question 13

If you use more bits per sample of audio…

Answer 13

It means that there are more options for the height of the wave (increases sample RESOLUTION), meaning that it can be more accurately measured when converting analogue sound to digital. However, it does increase the file size of the image

Question 14

What is sample rate measured in?

Answer 14

Hertz (Hz)

Question 15

So in sample rate, what does 1Hz mean?

Answer 15

1 Sample per second

Question 16

What is another word for Sample Rate?

Answer 16

Frequency

Question 17

What does the frequency affect in audio?

Answer 17

It affects the level of detail in the digital representation

Question 18

How to measure the file size for sound?

Answer 18

Sample resolution x Sample rate x Seconds

Question 19

How to calculate the image size?

Answer 19

Width x Height (Pixels) - Resolution

Question 20

What does lossy compression in sound mean?

Answer 20

• Permanently removes some data in order to compress
• Then creates a file with the remaining data and uses algorithms to guess lost data
• The uncompressed data will not be the same as the original, Quality will be removed from the upper and lower frequencies

Question 21

Lossy Compression in an Image?

Answer 21

• Some data is permanently removed
• Bit Depth is lowered (Similarly coloured pixels will be made the same colour)
• Smaller file size, but loss of quality

Question 22

Lossless Compression?

Answer 22

• No data is permanently removed
• Just finds a better way of saving storage, by grouping repeated data together in Run Length Encoding

Question 23

Huffman trees?

Answer 23

• Analyses the frequency at which characters in a text are used
• Characters are placed in a binary tree, where the most frequently used are placed near the top
• It is a representation of an algorithm that compresses data without losing it

Question 24

What does the Operating System manage?

Answer 24

• Manages how programs use RAM
• Manages Peripherals
• Manages Applications
• Provides Security
• CPU Management

Question 25

Examples of OS?

Answer 25

Windows, IOS

Question 26

RAM?

Answer 26

• Can be read from and written to
• Fast Access
• Contains things rnnn

Question 27

ROM?

Answer 27

• Data that needs to be permanently held in memory
• (BIOS)

Question 28

When is virtual memory used?

Answer 28

When RAM is filled up, it is uploaded to into secondary storage (Virtual Memory), but the access will be smm slowerrrrr

Question 29

What affects CPU speed?

Answer 29

• Number of Cores
• Clock Speed
• Cache Size

Question 30

Embedded Systems?

Answer 30

• Has a single microprocessor
• Carries out very specific tasks
• Bespoke operating system
• No Secondary Storage
• Program held in ROM
• RAM is used to accept user input