1. Introduction to Computer Science

2. What is Computer Science?
The study of processes that transform information
Related Fields:
Computer Engineering
Information Technology

3. Programming Languages
Machine Language
Assembly Language
High-Level Language
Machine language is written using binary code. Computer's native language. Consists of a fixed set of simple instructions that manipulate memory and machine registers. Machine language is also called object code.
Assembly language is machine language in human-readable form. Think of it as 'decoded' machine language. Same set of instructions. A program called an assembler performs the simple translation to machine language.
High-level languages like Basic, C#, and Java contain powerful instructions called source code that typically translate to several machine instructions. A compiler program performs the translation to machine language.

4. Executing Programs
CPU does not understand high-level programming languages
Programs in high-level languages must be either
Translated to machine language using a ______________
Interpreted "on the fly" using an ______________
What are the benefits / tradeoffs?

5. Python Invented by Guido van Rossum in 1990’s Popular Cross Platform
Used for:
Scripting and System Administration
Scientific computing
Web applications
Powers many Google apps

6. Python Programs Stored in files with a ______ extension
Executed using Python interpreter

7. Let’s Program!
Meet the Turtle

8. A Complete Python Program
# Make the turtle move import turtle size = 100 turtle.forward(size) turtle.right(90) turtle.forward(size * 10)

9. Python Programs Python programs consist of Comments Statements
# A comment starts with a hash mark
# Comments are notes for the programmer, and are ignored by the Python interpreter
Statements
import turtle
turtle.forward(size)