1. Chapter 1 Introduction to Computer Science
AP Computer Science
Chapter 1
Introduction to Computer Science

2. 1.1 Through 1.4 Nothing in life is obvious
Computers are faster, more accurate, and don’t forget information
What to do? Ask questions, listen to explanations (maybe more than once), read, practice and give effort

3. What else requires effort???????
Basketball, football, driving…
This results in success

4. How do we succeed in APCS?
Listen to teacher notes
Reading chapter-Reading Quiz
Getting help from another
Type in program examples
Observe the results
Change some of the statements
Observe what happens
**Practice on your own-REREAD

5. What doesn’t work in APCS
Cramming
Having someone else do your work
Copying assignments
Getting excessive help
**Suggestions from past students

6. Chapter 1 Lessons 1.5
Morse code, short and long signals (no record of signal, can miss pauses in between)
**“Objects First” Activity

7. Lessons 1.6 Electronic memory uses on/off
Magnetic hard drives have on/off
8 light bulbs create 256 different combinations (use 0 for off, 1 for on)
Off,on,off,off,off,off,off,on
(8 bits = 1 byte)

8. Numbers in base ten and base two
Base ten consists of numbers 0,1,2,3,4,5,6,7,8,9 then uses two digits like 10,11,
Base two consists of numbers 0,1 then uses two digits like 10,11,

9. Base ten and Base two (on board)
2 x 102 +
6 x 101 +
1 x 100
101 base 2 =
1 x 22 +
0 x 21 +
1 x 20 = 5 base 10
**Extra practice 10 to 2; 2 to 10

10. Bits, bytes, and codes
A single bulb can be on or off which is called a binary digit or bit (originally one vacuum tube)
Eight lights or bits is a byte
1 byte can only represent 256 characters (ASCII)
2 bytes is used for Unicode or 65,536 characters
**Bit competition

11. Memory and Storage 1.7
Operating System provides user interface and manages CPU
Motherboard – main board consisting of chips of silicon
RAM – stores information temporarily (Random Access Memory)
ROM – store permanent information (Read Only Memory)
CPU – brains of the computer (Central Processing Unit)

12. Memory is measured in bytes
KB–KiloByte 1,024 or 210
MB–MegaByte (1,048,576) or 220
GB–Gigabyte(1,073,741,824) or 230
TB-Terabyte(1,099,511,627,776)240 PB EB
**Hw. Ex

13. Secondary Storage 1.8/1.9 Hard drives, diskettes, tapes, CDs
Tapes and disks store iron oxide particles that are magnetically charged + or –
CDs are coded with areas that reflect and absorb light
Hardware vs. software
**Hw

14. Programming 1.10
Program – lists a sequence of instructions that allows the computer to perform a desired task
**Robot activity
**Algorithms-driving instructions

15. 1.10 Programming Languages
Assembly language used mnemonics for instructions ex. Mov AX,1234 also used Hexidecimal
Java is Object Oriented Programming (OOP)
Originally called OAK released as Java in 1995 and used in APCS 2003
*Can run on any platform and compatible with web pages
Python CS2

16. Lesson 1.11 Grace Hopper-Navy lieutenant who developed COBOL
Low-level and High-level Languages
FORTRAN – first successful programming language for the math and science community
BASIC –college students
Pascal, C, OOP

17. Other Languages, Hardware, Software
C++ - OOP and old way
Python in College/next year
Read on your own about networking

18. Some Key Events in Computer History
1842, Ada Lovelace designs programs that work on Charles Babbage’s analytical machine
1954, Fortran (Formula Translator) invented and is first commercially successful programming language for engineers and mathematicians
1958/1962 First video game called Tennis for Two.
1959, COBOL (Common Business Oriented Language) Grace Hopper
1979, Visicalc, Wordstar
1981, MS-DOS, Microsoft

19. Base sixteen or hexidecimal
0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F
Any group of 4 base-2 digits corresponds to one base-16 digit
1111 base 2 = F base 16
Base conversions practice and quiz
**Hw
F F =