bit, binary, bytes, unicode, ASCII, Typed arrays, buffers & how characters are displayed

Question 1

When will we encounter Typed arrays?

Answer 1

When working with WebGL, Canvas, Web Audio API, xhttpRequets, Fetch API, websockets, Web workers, Media Source API and file APIs

Question 2

When you created a typed arrays and setup the dataviews to access them what are the values initialized as?

Answer 2

0

Question 3

What are typed arrays?

Answer 3

Typed Arrays are ways to store a whole bunch of bytes as one big block and access them as if it where an array. Every single byte will be one value you put in an array buffer.

Typed arrays are a good way for javascript to deal with binary data.

Question 4

What are dataviews used for?

Answer 4

We access typed arrays with a data view that allows us to read and write the values that are inside of the typed arrays.

Question 5

How do we create a new typed array?

Answer 5

let buffer = new ArrayBuffer(16);

https://www.youtube.com/watch?v=UYkJaW3pmj0

Question 6

How do we create a new dataview?

Answer 6

let dv = new Dataview(buffer);

Question 7

What is a byte?

Answer 7

A group of binary digits, a group of 8 bits equals a byte and can represent 255 at a max.

The largest integer that can be represented in one byte is: 11111111 which is 128+64+32+16+8+4+2+1 = 255. Thus, the largest decimal integer you can store in one byte is 255. (in an unsigned byte)

Question 8

What is a bit?

Answer 8

A bit is the smallest unit of storage. A bit stores a 0 or 1. Anything with two separate states can store 1 bit
In a chip: electric charge = 0/1.

A bit is too small to be much use beyond this.

Question 9

Typically how much information can be displayed with 1 byte?

Answer 9

1 byte is enough space to hold about 1 typed character e.g B,X, or $

Question 10

What is ASCII Code?

Answer 10

ASCII is an encoding representing each typed character by a number
Each number is stored in one byte (so the number is in 0..255)

Question 11

What is Unicode?

Answer 11

“Unicode” is an encoding for mandarin, greek, arabic, etc. languages, typically 2-bytes per “character”

Question 12

How many bytes can the different measures of storage take?

Answer 12

Kilobyte, KB, about 1 thousand bytes
Megabyte, MB, about 1 million bytes
Gigabyte, GB, about 1 billion bytes
Terabyte, TB, about 1 trillion bytes (rare)

Question 13

What is a byte used for?

Answer 13

good at using the bits to store information. E.g

Really good for storing characters/letters, images, etc.

Question 14

Source

Answer 14

https://web.stanford.edu/class/cs101/bits-bytes.html