Introduction to ProgrammingHistory of programming

The first programmer

The first programmer was a woman – Ada Lovelace

Who made the first computer??

http://www.youtube.com/watch?v=tzUbxALPcyw

What is programming?

Programming is breaking a task down into small steps

Why learn to Program?

Programming really is fun

Programmers make lots of money

Programming is very intellectually rewarding

Programming makes you feel superior to other people

Programming gives you complete control over an innocent, vulnerable machine, which will do your evil bidding with a loyalty not even your pet dog can rival.

What makes a good programmer?

There are a few traits which might indicate that the person would be a good programmer:

Logical

Patient

Perceptive

At least moderately intelligent

Enjoys an intellectual challenge

Star Trek fan

Female *

Female *

Actually, males and females make equally good programmers.

It's true that there are currently more male programmers than female, which is strange given that one of the first ever programmers (Ada Lovelace) was female.

How to program?

Here's a quick overview of the process:

Write a program.

Compile the program.

Run the program.

Debug the program.

Repeat the whole process until the program is finished.

Write a program

Choose a programming language .. There are many to choose from: Java C C++ Python

Create a program is usually called source code, or just code.

Compile a program

In order to use a program, you usually have to compile it first.

When you write a program, it's not yet in a form that the computer can use.

Computers actually only understand lots of 1s and 0s in long streams, known as binary

You can't very well write programs using only vast amounts of 1s and 0s, so you write it in a more easily-understood form (a programming language)

Then you convert it to a form that the computer can actually use.

This conversion process is called compiling, or compilation.

Run the program

Once you have compiled the program into a form that the computer can use, you want to see if it works:

This is called running the program, or sometimes executing it

Debugging

It refers to fixing errors and problems with your program.

A problem in a program is known as a bug in a program

Scripting Languages

You've perhaps heard about something called scripting, or maybe you've heard of languages like JavaScript, AppleScript, Tcl and others (those languages are called scripting languages).

Scripting is essentially a type of programming

Scripting languages tend to be interpreted rather than compiled, which means that you don't need to compile them - they're compiled "on the fly”

The fact that scripting languages are interpreted generally makes them slower than programming languages for intensive operations (like complex calculations)

Scripting languages are often easier to learn than programming languages, but usually aren't as powerful or flexible

For programming things like applications for personal computers, you'll need to use a programming language rather than a scripting language

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Programming Languages:

Machine Language

Assembly Language

High level Language

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Machine Language

The fundamental language of the computer’s processor, also called Low Level Language.

All programs are converted into machine language before they can be executed.

Consists of combination of 0’s and 1’s that represent high and low electrical voltage.

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Assembly Language

A low level language that is similar to machine language.

Uses symbolic operation code to represent the machine operation code.

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High Level Language

Computer (programming) languages that are easier to learn.

Uses English like statements.

Examples are C ++, Visual Basic, Pascal, Fortran and …....

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Program Development Cycle:

1. Analyze: Define the problem

2. Design: Plan the solution to the problem

3. Choose the Interface: Select the objects

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Program Development Cycle:

4. Code: Translate the algorithm into a programming language.

5. Debug and Test: Locate and remove any errors in the program.

6. Complete the Documentation: Organize all the materials that describe the program.

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Programming Tools:

Flowchart

Pseudocode

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What is a flowchart?

Logic diagram to describe each step that the program must perform to arrive at the solution.

A popular logic tool used for showing an algorithm in graphics form.

Chapter 2- Visual Basic Schneider

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Purpose of Flowcharting:

An aid in developing the logic of a program.

Verification that all possible conditions have been considered in a program.

Provides means of communication with others about the program.

A guide in coding the program.

Documentation for the program.

Flowchart

Turn A/C off(process)

False

Turn on A/C(process)

True

Temp > 25

(decision)

End

Start

Temp(input)

The flow chart is made up of an input, decision and the alternative processes or actions.

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Example of Flowchart to show changing the score

Start

Set Score counter = 0

If Collides with Asteroid

Change score

Yes

Display score

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What is a Pseudocode?

A program design technique that uses English words.

Has no formal syntactical rules.

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Example of Pseudocode: Determine the average grade of a class:

Declare variable scoreSet score variable to 0If spaceship collides with the asteroid Get the current score Increment the score Output/display new score on the stage

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Example of Pseudocode:

Determine the average grade of a class:

Do while there are more data Get the next Grade Add the Grade to the Sum Increment the CounterLoopCompute average = Sum / CounterDisplay average

Home Learning Task…..See Grid

Useful Resources

What is computer programming ? http://www.youtube.com/watch?v=OWsyrnOBsJs