Computer Software System and application software interface between

Computer Software

System and application software interface between end users and computer hardware End users Application Software System Software Computer Hardware OS General purpose/Application specific Managers/Programmers

What is a SOFTWARE? - It directs the performance of a particular use or application of a computer to meet the information processing needs of the users, 2 types of software 1. system 2. application

SYSTEM SOFTWARE: Computer System Management System �System Software – programs that manage and support the resources and operations of a computer system as it performs various information processing tasks. �Application Software – programs that directs the performance of a particular use, or applications of a computer to meet the information processing needs of end users.

What is an operating system? An operating system is an integrated system of programs that manages the operations of the CPU, controls the i/o and storage resources and activities of the computer system.

Importance of the OS Used to maximize the productivity of a computer system by operating it in the most efficient manner. 2. It minimizes the amount of human intervention required during processing. 3. It helps your application program to perform common operations such as: 1. 2. 3. Entering of data Saving and retrieving of files Printing/displaying of output

Five basic functions of an OS 1. 2. 3. 4. 5. Provides user interface – end user/system communications Resource management – managing the use of hardware resources Task management – managing the accomplishment of tasks File management – managing data and program files Utilities and support – providing a variety of support services

The graphical user interface User interface part of the OS that allows you to communicate with it so you can load programs, access files and accomplish other tasks. 3 main type of user interface 1. Command-driven 2. Menu-driven 3. GUI

APPLICATION SOFTWARE: End User Application software consists of programs that direct computers to perform specific information processing activities for end-users. Also called as application packages – because they direct the processing required for a particular use that end-users want to accomplish.

Application packages Word processing package – programs that computerizes the creation, editing and printing of documents by electronically processing text data. 2. Electronic spreadsheet package – are application programs used for analysis, planning and modeling. They provide an electronic replacement for more traditional tools such as paper worksheets, pencils and calculators. 3. Graphics packages – convert numeric data into graphics such as line charts, bar graphs and pie charts. 4. The software suite – combines several individual packages that shares a common GUI. 1.

Developing Information System Solutions

The system development cycle System development cycle phase 1. Investigation – problem determination, feasibility study. 2. Analysis – Analyze the needs of end-users, develop a functional user requirements. 3. Design – specification of hardware, software, people and data resources 4. Implementation – system testing and training. 5. Maintenance – system modification.

FEASIBILITY STUDY �A preliminary study to investigate the information needs of prospective users and determines the: �Resource requirements �Costs �Benefits �Feasibility

Ways to gather information for systems development �Interviews with the employees, customers and managers. �Questionnaires to appropriate end users in the organization. �Personal observation �Examination of documents, reports, procedures manuals and other documents.

Cost and benefit study �It typically included in a feasibility study “if costs and benefits can be quantified, they are called tangible, otherwise, intangible” Tangible cost: Cost of hardware and software, employees and salaries Intangible cost: Loss of customer’s goodwill or employees morale

Tangible benefits: Decrease in payroll cost, decrease in inventory. Intangible benefits: Better customer services

The feasibility of a system Organizational feasibility – how well the proposed system supports the objectives of an organization. 2. Economic feasibility – is concerned with whether expected cost saving, revenues, investments. 3. Technical feasibility – can be demonstrated if reliable hardware and software capable of meeting the needs of a proposed system. 4. Operation feasibility – willingness and ability of the management, employees, customers and suppliers to use and support the proposed system. 1.