12/4/20151 Introduction To Computer Science Bina Ramamurthy

2 Objectives 4 Understanding of basic terminology for computers. 4 Understanding problem-solving methodology using a computer

3 Computing Systems: Hardware and Software 4 A computer is a machine designed to perform operations specified with a set of instructions called a program. 4 Hardware refers to the computer equipment. –keyboard, mouse, terminal, hard disk, printer 4 Software refers to the programs that describe the steps we want the computer to perform.

4 Computer Hardware 4 CPU - Central processing unit 4 ALU - Arithmetic and logic unit 4 ROM - Read only memory 4 RAM - Random access memory CPU Internal Memory Input Output Control ALU External Memory

12/4/20155 Terminology 4 Program : a set of instructions given to a computer to accomplish a certain task. –Ex: automated payroll computation 4 Hardware : physical (tangible) components that make up a computer system. –Ex: keyboard, disk drive, x-box 4 Software : programs that run the computer and those that are run by the computer. –Ex: operating system (Unix, Windows), wordprocessor, Halo 4 Computer system : Hardware and software taken together is referred to as a Computer System.

12/4/20156 Steps in Software Development 4 Clear understanding of the problem : Problem Specification. 4 Careful solution design paying attention all the constraints : Robust Algorithm Design. 4 Transform algorithm into a program : Abstraction and coding. 4 Complete debugging : Error removal. 4 Thorough testing : Make sure it works for all cases 4 Maintenance dictated by the environmental changes and time.

12/4/20157 The Programming Language “Whenever you are developing something new, you have tasks. You have to create a new subject matter. You have to create a language which is appropriate to discuss the subject matter. Many people are insufficiently aware of the second obligation.” ---Famous Computer Scientist Dijkstra This supports our move from Pascal  Modula-2  C++  Java  Python

8 Executing a Computer Program 4 Compiler –Converts source program into form that hardware can understand and execute CompileExecute Java language program Progr am output Input data

12/4/20159 What has CS113 to offer? Problem Solving OO Design Prog. Lang Algorithms Programming Environment Special Features -- Design -- Tools -- Techniques -- Class libraries -- Class -- Object -- Methods -- Attributes -- Relationships -- Encapsulation -- Inheritance -- Polymorphism -- Elements -- Control Structures -- Data Structures -- JDK 6 or above -- Greenfoot IDE -- Graphics CS113

10 keywords for today 1. Computer system 2. Hardware 3. Software 4. Problem solving 5. Design 6. Programming language 7. ALU (Arithmetic Logic Unit) 8. CPU (Central Processing Unit) 9. Block diagram of a computer 10. Compile (a program) 12/4/201510

12/4/ Your responsibilities 4 Plan your time. 4 Attend all the lectures and the recitations. 4 Read the text before every lecture. 4 Work individually on the projects : no group work is allowed. 4 Note that as the semester progresses, the complexity of the problems you will be required to solve will increase.

12/4/ Before next week.. 4 Buy the book or ebook. 4 Read Ch. 1 of the book. 4 CSE113 B : AM 4 CSE113A : 2.00 – 2.50 AM 4 Buy TophatMonacle and register yourself 4 We will help you with Greenfoot installation during next week’s lab/recitation