AP CSP Units 1-3 Study Guide

What is abstraction? Why does abstraction help programmers in collaboration?

What is abstraction? Why does abstraction help programmers in collaboration?

complex things made simple;

it helps by adding to existing code and lets programmers focus on the more important/special parts of their code

What does an onEvent code look like? What does it do?

onEvent("id", "type", "callback");

it tells the computer what to change after a user inputs something (like a click) by having an output

What is top-down design?

a way of designing your program by starting with the biggest problem and continuing to break it down into smaller pieces that are easier to solve

Put kilobytes to terabytes in order from least to greatest.

kilobyte, megabyte, gigabyte, terabyte

What are the benefits and negatives of lossy compression?

benefit: saves storage by reducing the number of bits

negatives: not reversible, some information is discarded

What are the benefits and negatives of lossless compression?

benefits: reversible, doesn't discard any information

negative: doesn't save much storage

What is the Domain Name System (DNS)?

converts URL addresses to the correct IP address; it allows routers to connect computers to websites

example: www.google.com > DNS > 192.168.1.15

What is Hypertext Transfer Protocol (HTTP)?

the protocol for transmitting web pages on the internet;

used for sending and receiving web pages and other web content

What is an IP Address?

the unique number assigned to each device on the internet

example: 192.168.1.15

What is a router?

computer that receives and redirects packets based on addressing info (IP address)

will either deliver a packet to its final destination or forward it to one of several other routers it is connected to

What is the Transmission Control Protocol (TCP)?

slow sending system but accurate through the numbering of packets for reassembly (useful for accuracy things like emails and photos);

multiple back and forth confirmations between sender and receiver;

when a packet is lost it resends the packet

What are packets?

all data is broken down into packets;

they are small chunks of data labeled with metadata;

transmitted over a network from one computer to another

What is network redundancy?

having multiple backups to ensure reliability during cases of high usage or failure

What is fault tolerance?

when a path has traffic or is out of service, additional paths are available;

this is because there are often redundant paths between two locations on the internet

What is protocol?

an agreed-upon set of rules that specify the behavior of some system

How many bits are in a byte?

8 bits

How many bytes are in a kilobyte?

1024 bytes (often rounded to 1000)

Why are we switching to IPv6 from IPv4?

IPv6 has the capability to provide an infinite number of addresses;

we are switching to accommodate the growing number of networks worldwide and help solve the IP address exhaustion problem

What is a subdomain?

a piece of additional information added to the beginning of a website's domain name;

example: https://photos.example.org

"photos" is the subdomain

What is metadata?

data that describes other data

What is RGB? What is the numerical value that represents RGB?

a color model that uses varying intensities of (R)ed, (G)reen, and (B)lue light which are added together to reproduce a broad array of colors;

the values range from 0-255:

rgb(243, 76, 100)

What is a problem in your code called?

bug

Fault tolerance and redudancy is achieved by…

the routers having multiple connections to each other.

how many bits represent a number

With 8 bits u can represent 256 values but highest # u can represent is 255

user datagram protocol (udp)

the speed of the packets arriving matters more than order (ex: livestreaming events)