The Graphical User Interface. Its main functions and tools

Nowadays most computers have a Graphical User Interface (GUI). It is a type of user interface which allows people to interact with electronic devices such as computers; hand-held devices such as MP3 Players, Portable Media Players or Gaming devices; household appliances and office equipment.

A GUI makes use a WIMP environment: Windows, Icons, Menus and Pointer. This type of interface is user-friendly, where system functions are accessed by selecting self-explanatory icons and items from menus.. A GUI offers graphical icons (graphic images (or intuitive symbols) representing programs, documents, an object or task.), and visual indicators (as opposed to text- based interfaces), typed command labels or text navigation to fully represent the information and actions available to a user. A graphical user interface saves a lot of time: you don't need to memorize commands in order to execute an application; you only have to point and click so that its content appears on the screen.

Double-clicking an icon opens a window that lets you work with different tools and menus. A window is a viewing area of the computer screen where you can see the contents of a folder, a file, or a program. Some systems allow several windows on the screen at the same time and windows can overlap each other.

The window on the top is the one which is "active", the one in use. By using different windows you can work on several documents or applications simultaneously. The actions are usually performed through direct manipulation of the graphical elements by the means of a drop-down menu, pop-up menu or pull-down menu (a list of options that appear below a menu bar when you click on an item). The tool for these manipulations is the pointer. The pointer is the arrow, controlled by the mouse, which allows you to move around the screen and choose options from menus. You operate the menu by pressing and

releasing one or more buttons on the mouse. Toolbar buttons are found at the top of a window, they take you to the Home folder and others. The dock is a set of icons at the bottom of the screen that give you instant access to the things you use most. When information has to be given to the user or input by the user, a window known as a dialog box is often used. It can contain a variety of elements to gather information from the user including: text boxes, drop- down list boxes, checkboxes and command buttons. A find dialog box is used to gather information from the user about the files they wish to find. All these activities take place on a desktop (the background screen that displays icons, representing programs, files and folders- directories or containers for documents and applications).

19. What is computer software and computer hardware? Main software characteristics. System software. Firmware. Middleware. Programming software. Application software. Software testing. Testware.

In computer science and software engineering, computer software is all computer programs

Computer software is so called to distinguish it from computer hardware, which encompasses the physical interconnections and devices required to store and execute (or run) the software.

Main software characteristics include:

· Software is developed and engineered.

· Software doesn't "wear-out".

Computer software or just software is a general term used to describe a collection of computer programs, procedures and documentation that perform some tasks on a computer system.

The term (computer software) includes:

System software such as operating systems, which interface with hardware to provide the necessary services for application software. It includes a combination of the following:

· device drivers operating systems servers utilities windowing systems

The purpose of systems software is to unburden the applications programmer from the often complex details of the particular computer being used, including such accessories as communications devices, printers, device readers, displays and keyboards, and also to partition the computer's resources such as memory and processor time in a safe and stable manner. Examples are - Windows XP, Linux and Mac.

Most software continues to be custom built.

Programming software usually provides tools to assist a programmer in writing computer programs, and software using different programming languages in a more convenient way.

The tools include:

· compilers debuggers interpreters linkers text editors

Application software allows users to accomplish one or more specific (not directly computer development related) tasks. Typical applications include:

· industrial automation business software computer games quantum chemistry and solid state physics software telecommunications (i.e., the internet and everything that flows on it) databases educational software medical software military software molecular modeling software image editing spreadsheet Word processing Decision making software

Firmware which is software programmed resident to electrically programmable memory devices on board mainboards or other types of integrated hardware carriers.

Middleware which controls and coordinates distributed systems.

Software testing is a domain independent of development and programming. It consists of various methods to test and declare a software product fit before it can be launched for use by either an individual or a group. Many tests on functionality, performance and appearance are conducted by modern testers with various tools such as QTP, Load runner, Black box testing to edit a checklist of requirements against the developed code.

Testware which is an umbrella term or container term for all utilities and application software that serve in combination for testing a software package but not necessarily may optionally contribute to operational purposes. As such, testware is not a standing configuration but merely a working environment for application software or subsets thereof. Softwareincludes websites, programs, video games, etc. that are coded by programming languages like C, C++, etc.

20. Software applications: word processors, spreadsheets, media players and database applications. Main characteristics, functions and tools.

Application software is any tool that functions and is operated by means of a computer, with the purpose of supporting or improving the software user's work. In other words, it is the subclass of computer software that employs the capabilities of a computer directly and thoroughly to a task that the user wishes to perform. Typical examples of software applications are word processors, spreadsheets, media players and database applications.

A word processor enables you to create a document, store it electronically on a disk, display it on a screen, modify it by entering commands and characters from the keyboard, and print it on a printer. The great advantage of word processing over using a typewriter is that you can make changes without retyping the entire document.

A spreadsheet program helps you manage personal and business finances. Spreadsheets, or worksheets, are mathematical tables which show figures in rows and columns.

A database is essentially a computerized record-keeping system.

Each unit of information you create is called a record and each record is made up of a collection of fields. Typically, a single record consists of a set of field names like: Title, First Name, Surname, Job Title, TelNo and ID. You fill in a form with the relevant information for each field to add a new record to the database. There are different data types.

Text - holds letters and numbers not used in calculations Number - can only hold numbers used in calculations and reports Memo - can store long texts Date/Time - a date or time or combination of both AutoNumber - assigns a number to each record OLE Object - (object linking and embedding) holds sounds and pictures

Yes/No - for alternative values like true/false, yes/no, on/off, etc.

Hyperlink - adds a link to a website

Media player is a term typically used to describe computer software for playing back multimedia files. Most software media players support an array of media formats, including both audio and video files.

21. Graphics software. Computer graphics categories: raster graphics and vector graphics. Image manipulation programs. Painting and drawing programs. Business graphics programs. Computer-aided design. Computer animation. Geographic information system.

Computer graphics are graphics created using computers and, more generally, the representation and manipulation of pictorial data by a computer.

The development of computer graphics, or simply referred to as CG, has made computers easier to interact with, and better for understanding and interpreting many types of data. Developments in computer graphics have had a profound impact on many types of media and have revolutionized the animation and video game industry.

Computer graphics can be classified into two distinct categories: raster graphics and vector graphics. these graphics types, you should be familiar with both.

A raster graphics image or bitmap is a data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium. Raster images are stored in image files with varying formats. A bitmap is technically characterized by the width and height of the image in pixels and by the number of bits per pixel (a color depth, which determines the number of colors it can represent).

Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical equations, to represent images in computer graphics. Vector graphics files store the lines, shapes and colours that make up an image as mathematical formulae. A vector graphics program uses these mathematical formulae to construct the screen image, building the best quality image possible, given the screen resolution

Image manipulation programs let you edit your favourite images. In digital editing, photographs are usually taken with a digital camera and input directly into a computer. Transparencies, negatives or printed photographs may also be digitized using a scanner, or images may be obtained from stock photography databases. With the advent of computers, graphics tablets, and digital cameras, the term image editing encompasses everything that can be done to a photo, whether in a darkroom or on a computer.

Painting and drawing programs, also called illustration packages, offer facilities for freehand drawing, with a wide choice of pens and brushes, colours and patterns. One example is Windows Paint.

Business graphics programs, also called presentation software, let you create pie charts, bar charts and line graphs of all kinds for slide shows and reports. You can import data from a database or spreadsheet to generate the graphs. Presentation software typically includes three major functions: an editor that allows text to be inserted and formatted, a method for inserting and manipulating graphic images and a slide-show system to display the content.

Computer-aided design (CAD) is the use of computer technology for the design of objects, real or virtual. CAD often involves more than just shapes. As in the manual drafting of technical and engineering drawings, the output of CAD often must convey also symbolic information such as materials, processes, dimensions, and tolerances, according to application-specific conventions.

CAD may be used to design curves and figures in two-dimensional ("2D") space; or curves, surfaces, or solids in three-dimensional ("3D") objects.

Computer animation (or CGI animation) is the art of creating moving images with the use of computers. It is a subfield of computer graphics and animation. Increasingly it is created by means of 3D computer graphics, though 2D computer graphics are still widely used for stylistic, low bandwidth, and faster real-time rendering needs. Sometimes the target of the animation is the computer itself, but sometimes the target is another medium, such as film. It is also referred to as CGI (computer-generated imagery or computer-generated imaging), especially when used in films.

A geographic information system (GIS), Technically, a GIS is a system which includes mapping software and its application to remote sensing, land surveying, aerial photography, mathematics, photogrammetry, geography, and tools that can be implemented with GIS software.

In simplest terms, GIS is the merging of cartography and database technology. Consumer users would likely be familiar with applications for finding driving directions, like a GPS program on their hand-held device. GPS (Global Positioning System) is the real time location component that uses satellites to show your current position, "where am I now" on your device. GPS technology is discussed in more detail later in this article.

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