Transcript Document

Introduction to
Computers and
Python
What is a Computer?


Computer- a device capable of
performing computations and
making logical decisions at speeds
millions times faster than humans.
Computer Program- set of
instructions that tells the computer
what to do.
Computer Programmers

The individuals that write programs
for the computer.

That’s what you will all be doing in
this course.



Hardware- devises that make up
the computer such as the
keyboard, screen, mouse, disks,
memory, CD-ROM, and processing
unit.
Software- The programs that run
the computer.
Current trend- as hardware costs
drop the cost for software rises.
Computer Organization
Six Logical Units


1. Input Unit- “Receiving Unit”.
Section of the computer that
obtains information.
Types of Input Devises
Keyboard
 Mouse
 Microphone
 Scanner
 Digital camera

2.
Output Unit- “Shipping” section .
Section of the computer that
takes information that the
computer has processed and
places it on various output
devises
Output Devises
Monitor, printer, audio-visual
devises.
3. Memory Unit



“warehouse section”- temporarily
stores data. The memory unit
retains information that has been
entered through the input unit.
Often called RAM- Random
Access Memory
Volatile- erased when machine is
turned off.
4. Arithmetic and Logic
Unit. ALU

“Manufacturing “ sectionResponsible for the performance of
calculations such as addition and
multiplication. It also contains the
decision mechanisms allowing the
computer to perform such tasks as
determining whether two items
stored in memory are equal.
5. Central Processing
Unit CPU


“administrative section’ This
section coordinates the operation
of the other sections.
Acts as the brain of the computer
telling it to use the appropriate unit.
6. Secondary Storage
Unit



“long-term warehousing” This
refers to the hard drive, disks,
network or other places data is
stored when not being actively
used.
Information in this type of storage
takes longer to access than
information stored in primary
storage
Not Volatile
Different Programming
Languages




Machine Language- the only language
a computer can understand directly.
Consists of a stream of numbers which
are ultimately reduced to 0’s and 1’s
This might be the machine code to add
two numbers together
00011101010
Every machine has a different machine
language



Assembly-used English like
abbreviations to represent
elementary operations of the
computer.
LOAD x,y
ADD x + y
Still different on every computer




High-Level Languages- a
programming language in which
single statements accomplish
substantial tasks.
Can be used on different computers
Compilers work as translation
programs converting high-level
language to machine language.
Sum= x + y
Python and other HighLevel Languages





Python was created from the start to be easy to
learn. Python programs are about the easiest to
read, write and understand.
Python is free.
Python is open source software. Any user can
extend Python
Used by thousands of professionals around the
world including NASA and Google.
Runs on different kinds of computers.

Other High-Level Languages

C, C++, Java, C#, Pascal, COBOL,
FORTRAN

Structured Programming- designig
programs so they are easy to
follow and easy to modify. Went
from general to more specific.
Programs were broken into
modules.
Questions

Computers can only understand their
native ______ language.

Computers process data under the
control sets of instructions called
computer _______.
Name the three types of languages
discussed in this chapter.
Programs that change high level
language to machine language are
called______.



Name two input and two output
devises.

Why is the CPU called the brain of
the computer?

What are the two types of
operations performed by the ALU?

In this class you will become____
programmers.