CSCI E-1a
Fall 2021
http://jrsacher.github.io/e1a
Contact Josh
General Information
Sections
Programming
Slides
Sandbox
Demo of compiled vs. interpreted languages
Quiz questions
- What is a Boolean expression?
A yes/no true/false statement. Often used with loops and conditionals (below).
- What is bytecode?
An intermediate code created from source code in interpreted languages such as Python which is then executed by a virtual machine
- What are loops and conditions?
Methods of controlling program flow. Loops let a chunk of code be repeated, while conditionals provide branching options.
- What does it mean for a program to be multithreaded?
More than one piece of code is being executed at the same time
- What is an event, in the context of programming?
A sort of notification sent from one thread to another
Web Development
Slides
Sandbox with example webpage
Resources
- W3 Schools
- HTML dog (links from the assignment)
Quiz questions
- What is a web server and what is a web client?
A web server is a computer that can listen for requests and then send websites back to a user. The client is your web browser (or another application) that makes the requests.
- Identify three different HTTP status codes and describe what they mean/represent.
See here for a list of codes
- What is a CSS selector?
A way of grabbing a particular piece of HTML and applying style to it
- In your own words, what is the action attribute of an HTML form used for?
The action attribute tells the webpage what to do on form submission
- What is the DOM? What might we use it for?
The Document Object Model is a tree-like structure for a webpage. It’s useful for CSS selectors, JavaScript, and more.
Assignment
- Start ASAP
- Look things up online!
- Be sure to use relative links so that it works on the Staff’s computers
Security
Slides
Quiz questions
- What is incognito mode? What privacy features might it offer?
The browser starts “clean” and any cookies, history, or information acquired during that session is removed on exit.
- How does a password manager work?
One master password protects a “vault” of other passwords, meaning you only have to remember a single password to access all login info for all sites.
- Why is it not a problem for me to release my public key, in a cryptography context?
The public key only allows data to be encrypted. The private key is needed for decryption.
Multimedia
Slides
Quiz questions
- How are MIDI files different from MP3 files for the same song?
While MP3 files are recordings of the song, MIDI files are instructions for a computer to play a song – similar to sheet music.
- In the context of digital audio, what are the sample rate and bit depth?
Sample rate is the number of audio snapshots/slices taken per second. Bit depth is a measure of how many bits are used to store each sample.
- In the context of RGB color, what is ff00ff, most likely?
Magenta! See here, for instance
- In the context of video compression, what are (and why might we want to use) keyframes?
Keyframes are complete images stored at regular intervals. After that, only the changes to the image(s) have to be recorded until the next keyframe. This allows us to use less data to store the same information.
Internet
Slides
Quiz questions
- Describe the difference between a cable modem and a router, in the context of home networking.
A router (wireless or otherwise) connects your devices to the modem. The modem is responsible for sending/receiving information. The two are sometimes housed in the same unit.
- Identify two port numbers that are commonly used, and what services/protocols use them.
See here and links therein.
- Why do we have multiple versions of the Internet Protocol?
We thought we had enough addresses for all the devices ever. It turns out we were wrong – internet connected refrigerators weren’t a thing when IPV4 was implemented.
Hardware
Slides
Quiz questions
- How would we represent the number “28” in binary?
| 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|
| 1 | 1 | 1 | 0 | 0 |
- Describe at least one key difference between RAM and hard disk
RAM is faster at data transfer and has less storage capacity. A disk will maintain its state when power is removed, but RAM is volatile – it can’t store anything without constant power.
- What is an operating system?
Software that sits between the user and hardware. Runs programs, manages resources, provides a user interface.
General Info
Contact Josh or all course staff
Sections (feel free to attend whichever is convenient):
- Zoom link – the same for all sections
- Wed 6:00 – 7:30 pm ET with Greg
- Thur 7:00 – 8:30 pm ET with Josh
Office hours:
- Office hours link
- Thur 6:00 – 7:30 pm ET with Josh
- Sun 11:00 am - 12:30 pm ET with Greg
- Potentially by appointment – ask your assigned TF