Tute-1-Computer Software

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1 System Software System software is computer software designed to operate the computer hardware and to provide maintain a platform for running application software. The most basic types of system software are: The computer BIOS and device firmware, which provide basic functionality to operate and control the hardware connected to or built into the computer. The operating system (prominent examples being Microsoft Windows, Mac OS X and Linux), which allows the parts of a computer to work together by performing tasks like transferring data between memory and disks or rendering output onto a display device. It also provides a platform to run high-level system software and application software. Utility software, which helps to analyze, configure, optimize and maintain the computer Compilers A compiler is a computer program (or set of programs) that transforms source code written in a programming language (the source language) into another computer language (the target language, often having a binary form known as object code). The most common reason for wanting to transform source code is to create an executable program. Interpreters An interpreter normally means a computer program that executes, i.e. performs, instructions written in a programming language. An interpreter may be a program that either 1. Executes the source code directly 2. Translates source code into some efficient intermediate representation (code) and immediately executes 3. Explicitly executes stored precompiled code made by a compiler which is part of the interpreter system Prepared by, T.Hewathanthrie Page 1

2 Compiler Translates the whole program at once to produce the object code. Therefore more Efficient. Can run the program independently Repeated executions, do not need retranslation Syntax and Semantic errors are detected early ( Before running) Execution speed is higher with compiler Run time memory requirement is less Source program need not to be given to the user Interpreter Translators execute the program statement by statement Always the program is run under the control of interpreter For each run need a translation Syntax and Semantic errors are detected only at run time Execution speed is lower More run time memory is required Needs to give the program to the user. Application Software Application software, also known as an application or an "app", is computer software designed to help the user to perform singular or multiple related specific tasks. It helps to solve problems in the real world. Examples include enterprise software, accounting software, office suites, graphics software, and media players. Application software is contrasted with system software and middleware, which manage and integrate a computer's capabilities, but typically do not directly apply them in the performance of tasks that benefit the user Tailor made Software/ Bespoke Software Bespoke software applications, written to meet specific client requirements, offer many advantages over standard, off-the-shelf software. Prepared by, T.Hewathanthrie Page 2

3 Advantages of Bespoke Software Bespoke software is easy to use because it works the way you work. You are in control - you can make the changes you require when you like. Bespoke software precisely matches your working practices, requiring less supervision and generating fewer errors Bespoke applications increase productivity by automating repetitive tasks. Your own software differentiates you from the competition with unique products and services. Business information is easier to understand because bespoke applications incorporate your business know-how. Information can be integrated from disparate existing applications. Ex: Accounting Packages, Library management Disadvantages of Bespoke Software 1. Cost Bespoke software will generally be more expensive to start using as it will involve a large initial investment into its development. However, once paid for it, it may not cost you anything further to use it. 2. Difficulty Selecting a Good Developer There are a lot of software development companies in the UK, some of which are great and some of which are very poor. Selecting a good software developer can be difficult, particularly if you have no experience in the software development process. If you choose a good software developer they will be able to produce a piece of software that will greatly enhance your business. However, if you choose a bad software developer it may cost you a lot of time and money to rectify the problems they have created. Prepared by, T.Hewathanthrie Page 3

4 3. Time Consuming Tute-1-Computer Software The development of bespoke software can take a long time to complete and may involve you allocating a lot of your time to the development process e.g. writing the brief, meeting with the developers, testing the system, providing feedback. Off the shelf Packages Commercial, off-the-shelf (COTS) or simply off the shelf (OTS) is a term defining technology which is ready-made and available for sale, lease, or license to the general public. The term often refers to computer software or hardware systems and may also include free software with commercial support. Advantages of Off-the-Shelf Software 1. Price Off-the-shelf software is generally cheaper than custom-built software as the development costs are spread amongst many customers. 2. Reliability Off-the-shelf software has been tried and tested both by the seller and by existing customers. 3. Readily Available Support There will generally be a wealth of support documentation available as there are lots of other users using the same software. You may also be able to find third-party training courses and discussion groups on the Internet. 4. Available Now You do not need to spend the time specifying the software and then waiting for it to be developed. It will be ready for you to use straight away. Ex: Office automation systems, Graphics, Medical/Biological systems, engineering systems. Prepared by, T.Hewathanthrie Page 4

5 Disadvantages of Off-the-Shelf Software Customization May Not Be Possible Off-the-shelf software is usually designed to be as flexible as possible so that it can suit the needs of the largest number of potential users. However, you may require the software to perform a task that is specific to your business which it is unable to do. It is unlikely that you will be able to get the publishers of the software to make any customizations for you. Change Business Processes If the software does not exactly fit your business processes you may be forced to adapt your business to fit the software. Overly Complex As the software is designed to accommodate a variety of users, it is likely that there will be large sections of the software that you are paying for but are not relevant to your organization. You may also find that these sections get in the way when you are trying to use the rest of the system. Little Competitive Advantage As your competitors can buy and use the same software, you will gain little competitive advantage from off-the-shelf software. Classification of Information 1. Manual Vs Computerized Information Manual is using old method without the help of the technology or maybe less to perform certain task or work. For example using type writer to write a report or keep documents in the paper folder. While computerized system is using latest technology of ICT to carry out various tasks that is more effective compare to manual system in terms of the productivity and time usage. Prepared by, T.Hewathanthrie Page 5

6 2. Accordingly to the Level of Management Information System Executive Support Management Information Description An Executive Support System ("ESS") is designed to help senior management make strategic decisions. It gathers analyses and summarizes the key internal and external information used in the business. A good way to think about an ESS is to imagine the senior management team in an aircraft cockpit - with the instrument panel showing them the status of all the key business activities. ESS typically involves lots of data analysis and modeling tools such as "what-if" analysis to help strategic decision-making. A management information system ("MIS") is mainly concerned with internal sources of information. MIS usually take data from the transaction processing systems (see below) and summaries it into a series of management reports. MIS reports tend to be used by middle management and operational supervisors. Prepared by, T.Hewathanthrie Page 6

7 Decision- Support Knowledge Management (KMS) Transaction Processing Office Automation Tute-1-Computer Software Decision-support systems ("DSS") are specifically designed to help management make decisions in situations where there is uncertainty about the possible outcomes of those decisions. DSS comprise tools and techniques to help gather relevant information and analyze the options and alternatives. DSS often involves use of complex spreadsheet and databases to create "what-if" models. Knowledge Management ("KMS") exist to help businesses create and share information. These are typically used in a business where employees create new knowledge and expertise - which can then be shared by other people in the organization to create further commercial opportunities. Good examples include firms of lawyers, accountants and management consultants. KMS are built around systems which allow efficient categorization and distribution of knowledge. For example, the knowledge itself might be contained in word processing documents, spreadsheets, PowerPoint presentations. Internet pages or whatever. To share the knowledge, a KMS would use group collaboration systems such as an intranet. As the name implies, Transaction Processing ("TPS") are designed to process routine transactions efficiently and accurately. A business will have several (sometimes many) TPS; for example: - Billing systems to send invoices to customers - to calculate the weekly and monthly payroll and tax payments - Production and purchasing systems to calculate raw material requirements - Stock control systems to process all movements into, within and out of the business Office Automation are systems that try to improve the productivity of employees who need to process data and information. Perhaps the best example is the wide range of software systems that exist to improve the productivity of employees working in an office (e.g. Microsoft Office XP) or systems that allow employees to work from home or whilst on the move. 3. According to the Function of the Information System 1. Office Information An office information system is an information system that uses hardware, software and networks to enhance work flow and facilitate communications among employees. Prepared by, T.Hewathanthrie Page 7

8 2. Transaction Processing A transaction processing system (TPS) is an information system that captures and processes data generated during an organization s day-to-day transactions. A transaction is a business activity such as a deposit, payment, order or reservation. 3. Management Information While computers were ideal for routine transaction processing, managers soon realized that the computers capability of performing rapid calculations and data comparisons could produce meaningful information for management. Management information systems thus evolved out of transaction processing systems. 4. Decision Support Transaction processing and management information systems provide information on a regular basis. Frequently, however, users need information not provided in these reports to help them make decisions. A sales manager, for example, might need to determine how high to set yearly sales quotas based on increased sales and lowered product costs. Decision support systems help provide information to support such decisions. A decision support system (DSS) is an information system designed to help users reach a decision when a decision-making situation arises. A variety of DSSs exist to help with a range of decisions. A decision support system uses data from internal and/or external sources. 5. Expert An expert system is an information system that captures and stores the knowledge of human experts and then imitates human reasoning and decision-making processes for those who have less expertise. 6. Integrated Information Usage of more than one of those information systems for the required purposes. Prepared by, T.Hewathanthrie Page 8