Punjab PSEB Matric Computer Science key terms

The chip that carries out the instructions of a program. It fetches each instruction, decodes it, performs arithmetic and logic operations, and controls the other parts of the computer.

The computer's main working memory. It holds the programs and data currently in use, can be read and written very quickly, and loses all its contents when the power is switched off.

Non-volatile memory whose contents are written during manufacture and normally cannot be changed by the user. It stores the firmware and startup instructions a computer needs before the operating system loads.

The main circuit board inside a computer. It carries the processor socket, memory slots, expansion slots and ports, and contains the wiring that lets every component exchange data and power.

Hardware used to enter data or commands into a computer, such as a keyboard, mouse, scanner, microphone or webcam. The device converts human actions into signals the computer can process.

Hardware that presents processed results in a form people can understand, such as a monitor, printer, speaker or projector. Output may be soft copy on screen or hard copy on paper.

Non-volatile storage that keeps data and programs permanently when the computer is switched off, for example a hard disk, SSD, pen drive or DVD. It is slower than RAM but much larger in capacity.

The main system software that manages hardware, memory, files and running programs, and provides the user interface. Windows, Linux and Android are examples; application software depends on it to run.

A way of working with a computer using windows, icons, menus and a mouse pointer instead of typed commands. It makes software easier for beginners to learn and use.

A named collection of related data stored on a storage device, such as a document, picture, song or program. Every file has a name and usually an extension showing its type.

A container on a storage device used to group and organise files. Folders can hold other folders, forming a tree-like structure that keeps related work together and easy to locate.

The short suffix after the dot in a file name, such as .docx, .xlsx or .jpg. It tells the operating system which program can open the file and what kind of content it holds.

The address showing where a file or folder sits in the storage hierarchy, for example D:\School\Notes\unit1.docx. It lists the drive and each folder in order down to the file.

A temporary holding folder where deleted files are kept. Items remain there until the bin is emptied, so a file deleted by mistake can usually be restored to its original location.

Application software for creating and editing text documents, with tools for formatting, spell checking, inserting tables and pictures, and printing. Microsoft Word and LibreOffice Writer are common examples.

The automatic movement of text onto the next line when the current line is full, without the user pressing Enter. Only a real paragraph break, made with Enter, starts a new paragraph.

The way text lines up against the page: left, right, centre or justified so that both edges are straight. Alignment is set for a paragraph and applies to all its lines.

The blank space between the edge of the paper and the text area of a page. Top, bottom, left and right margins can be set separately, usually in centimetres or inches.

Text or objects repeated at the top (header) or bottom (footer) of every page, typically page numbers, document titles or dates. They are typed once and appear throughout the document.

A feature that combines one main document with a list of records, such as names and addresses, to produce many personalised copies, for example letters, envelopes, labels or certificates.

Application software that stores numbers and text in a grid of rows and columns and recalculates results automatically when data changes. Excel and LibreOffice Calc are common examples.

The basic box of a spreadsheet, formed where a row and a column meet. It can hold a number, text, date or formula and is named by its column letter and row number.

A rectangular block of two or more selected cells, written with the top-left and bottom-right addresses separated by a colon, such as A1:C10. Functions and charts often work on ranges.

An instruction in a spreadsheet cell that begins with an equals sign and calculates a result from values, cell references and operators, for example =A2*B2. The result updates whenever inputs change.

A built-in spreadsheet command with a name that performs a calculation on given values, such as SUM, AVERAGE, MAX or IF. Functions save the effort of writing long formulas by hand.

A cell reference written with dollar signs, like $B$4, that stays fixed when the formula is copied to other cells. The row part or column part can also be locked on its own.

A visual representation of spreadsheet data such as a column, bar, line or pie chart. Charts make comparisons, patterns and trends easier to see than a plain table of numbers.

Application software for building slide shows that combine text, images, sound and video for an audience. PowerPoint, LibreOffice Impress and Google Slides are common programs.

The top-level slide that stores the design, fonts, colours and placeholder positions used by every slide in a presentation. Editing it changes the appearance of all slides that follow it.

The effect that plays when one slide changes to the next during a slide show, such as a fade or push. A transition applies to a whole slide, not to items inside it.

An effect applied to text, pictures or other objects within a slide so they appear, move, change or disappear. Animation controls the order and timing of items on a single slide.

Content that combines two or more media types, such as text with pictures, audio, video and animation. In presentations it makes information more engaging but can make file sizes large.

A worldwide network of interconnected computers that exchange data using common rules called protocols. It carries services such as the web, email, file transfer and video calling.

Uniform Resource Locator, the address of a resource on the web, such as https://www.pseb.ac.in/index.html. It shows the protocol, the domain name and the path of the page.

Software used to request, download and display web pages, such as Chrome, Firefox or Edge. It reads HTML code and turns it into the formatted page you see on screen.

Electronic mail: a service for sending messages and attached files from one user's mailbox to another over the Internet, using an address of the form username@domain.

Unsolicited bulk email, usually advertising or fraudulent, sent to large numbers of recipients without their consent. Spam filters move such messages into a junk or bulk folder.

A trick in which a fake email, message or website pretends to be genuine in order to steal passwords, card numbers or other private data. Never click such links or share credentials.

Harmful software installed without the user's informed consent, including viruses, worms, trojans, spyware and ransomware. Antivirus software and cautious downloading reduce the risk of infection.

Hardware or software that checks network traffic against set rules, blocking unauthorised connections while allowing approved ones. It acts as a barrier between a trusted network and the Internet.