Held: Monday, 25 January 2016

On to Outline 02 - An Introduction to Linux.

Summary

We begin the class by exploring the definition of computer science and by trying to write some basic algorithms.

Related Pages

• Post-class reading: Parts of Algorithms
• Assignment 1: Introductory Survey
• EBoard 1 (Source 1)

Overview

• Introduction: What is CS?
• Exercise: An everyday algorithm.
• Debriefing on exercise (continues next class).

Administrivia

• Welcome to CSC 151!
• Five handouts (please take when you enter the room).
  • A playing card.
  • Assignment 1
  • Departmental academic honesty policy.
  • Reading: Linux
  • Reading: Algorithms
• We are your support team: Sam, Sarah, Evan, Renn, and Zachary
• Reminder: CSC 151 meets on Tuesdays (as well as Mondays, Wednesdays, and Fridays).
• Office hours: MTWF 10-11, Tu 1-2. Sign up at http://rebelsky.youcanbook.me.

Upcoming Work:

• Readings for class 2: Linux, Algorithms.
• Assignment 1 due Tuesday at 10:30 p.m.

An Introductory Question

• Rather than telling you exactly what the class is about, I'm going to start the class with a question for you.
  • The question will help ground the class.
  • The question will begin to get you used to some aspects of my teaching style (particularly my reliance on recitation-style work).
  • The question will test your abilities as a liberal artist.
• What is Computer Science?
• I will give some of my own responses after I've heard some of yours.

What is CS?

• Computer scientists differ in how they define the discipline. However, most would agree that, at least in part,

  Computer science is the study of algorithms and data structures.

• By "algorithms", we mean sets of instructions that can be used to solve problems.
  
  • Some problems are mathematical. For example, you might write an algorithm to find the square root of a real number.
  • Other problems deal with textual information. For example, you might write an algorithm that tells how to find a name in the phone book.
  • Still other problems deal with graphical information. For example, you might write a program that finds text in an image (and then figures out what the text is).
  • Clearly, you can write algorithms for a wide variety of problems.
• By "data structures", we mean mechanisms for organizing information. For example, we organize some information in lists, other information in tables, and other information in more complex structures.
• By "study", we mean specify, design, describe, evaluate mathematically, evaluate experimentally, implement in software, implement in hardware, prove properties, consider applications and implications, and much, much more.
• In our studies, we rely on the tools and techniques from a number of other disciplines.
  
  • From mathematics, we take proof techniques, formal language for describing problems and solutions, and even core ideas.
  • From science, we take an experimental approach. We show that an algorithm is "correct" by constructing a variety of experiments.
  • From engineering, we take techniques for designing and constructing things.
  • From psychology and the social sciences, we take techniques for understanding the relationship of our work to human endeavors.
• These diverse perspectives and skill sets make CS interesting and challenging.
• Our European colleagues often refer to the discipline as "Informatics" (that is, implying the study of information), and I will admit that I have come to prefer the term because it distances us a bit from both computers (we are broader than the technology) and from science (since we do not necessarily emphasize the scientific method).

An Everyday Algorithm

• We'll explore the problems of writing clear instructions through a simple exercise.
• Challenge: Write a clear, unambiguous, and detailed set of instructions for making a nut butter and preserves sandwich.
• Format: Work in groups of about four.
  • I will distribute playing cards to help you identify those groups.
• Each group will write its solution on one of the four boards.
• SamR will play the role of the sentient, but malicious and clueless "follower of instructions".

Debriefing

• We will consider some of the implications of the activity today.
• Model: Discuss implications in your small group. Then pick a few important topics to share with the larger group.
• We will continue debriefing in the next class period.