Introduction to Computing - Preliminary Examination Preparation

Computer Literacy

• Knowing how to use a computer to perform basic tasks, including operating software systems, platforms, and computer programs commonly used in the workplace.

What is a Computer?

• An electronic device that inputs data, processes data, outputs information, and stores information.

• Controlled by programmed instructions.

• Generally, a device that accepts input, processes it, stores data, and produces output.

Information processing

refers to the manipulation of digitized information by computers and other digital electronic equipment.

DATA

A collection of independent and unorganized facts.

INFORMATION

Processed and organized data presented in a meaningful form.

DATA PROCESSING

The course of doing things in a sequence of steps.

HARDWARE

The tangible part of a computer system.

SOFTWARE

The non-tangible part that tells the computer how to do its job.

PEOPLEWARE

People who use and operate the computer system, write computer programs, and analyze and design the information system.

input
process
store
output

Functions of an Information Processing System

input — processing — output — store

Information Processing Cycle

Input

component of of Information processing cycle where Data provided to the computer. Examples include: words, numbers, pictures, audio signals, signals from other computers, temperature from sensors.

Processing

The manipulation of data. Examples include: arithmetic calculations, sorting, modifying pictures, drawing graphs. A computer program or software is a series of instructions that tell a computer how to carry out a processing task.

output

The result produced by a computer after processing the data. Examples include: images on a monitor, printed documents, sounds, signals to device controllers. Output devices display, print, or transmit the results after processing.

Storage

Location where to save the output. Examples include: SSD, HDD, Flash Drive, CDs, Memory Cards.

System software operates computer hardware

application software performs specific tasks for users

System Software vs. Application Software

System software

operates computer hardware

application software

performs specific tasks for users

Algorithm

• An organized sequence or list of clear steps or operations needed to solve a given programming problem.

• Any well-defined computational procedure that takes some value(s) as input and produces some value(s) as output.

• The sequence of computational steps that transform the input to output.

• Input

• Process (Steps or Instructions)

• Output

Components of an Algorithm

Speed and memory

• Algorithms are chosen based on their efficiency.

• Efficiency is measured by ____ and ____

1. Obtain a description of the problem.

2. Analyze the problem.

3. Develop a high-level algorithm.

4. Refine the algorithm by adding more details.

5. Review the algorithm.

Algorithm Formulation Steps

Software Development Life Cycle (SDLC)

• A framework that defines the steps involved in the development of software at each phase.

• Covers the detailed plan for building, deploying, and maintaining the software.

• Defines the complete cycle of development, including all tasks involved in planning, creating, testing, and deploying a software product.

Requirement Gathering and Analysis

Design

Implementation/Coding

Analysis of the Solution

Testing, Debugging, and Integration

Maintenance

Software Development and Stages

Flowchart

• A diagram that depicts a process, system, or computer algorithm.

• Widely used to document, study, plan, improve, and communicate complex processes.

• Uses rectangles, ovals, diamonds, and arrows to define steps, flow, and sequence.

Terminal Box / Terminator

a flowchart symbol where it Represents the starting or ending point of the system.

Initialization Box

a flowchart symbol where it Prepares all variables that will hold some values.

Input / Output Box

a flowchart symbol where it Represents a printout, such as a document or a report.

Process Box

Indicates some particular operation.

Flow Lines

Represent the flow of the sequence and direction of a process.

On-Page Connector/Reference

Indicates that the flow continues on a matching symbol containing the same letter somewhere else on the same page.

Off-Page Connector/Reference

Indicates that the flow continues on a matching symbol containing the same number somewhere else on a different page.

Decision Box

Represents a decision or branching point.

Pseudocode

• An informal high-level description of the operating principle of a computer program or other algorithm.

• Uses the structural conventions of a normal programming language, but is intended for human reading rather than machine reading.

• start

• end

• initialize

• compute

• read or input

• write or output

Basic Terms and Uses

• for & endfor

• while & endwhile

• if & endif

• case & endcase

Terms Used for Conditional and Looping