The "@" symbol is used to separate the username of an email address from the domain name of the Internet Service Provider (ISP) or email service provider. For example, in the email address "username@example.com," "username" is the username of the email account, and "example.com" is the domain name of the email service provider, separated by the "@" symbol.

The built-in memory of a computer typically refers to RAM (Random Access Memory). RAM is a type of volatile memory that the computer uses to temporarily store data that is actively being used or processed. It provides fast access to the data the computer needs to perform tasks, and its content is erased when the computer is powered off.

An output device that is used for TV-like displays and shows the output on the screen is indeed called a monitor. It is also commonly referred to as a visual display unit (VDU). Monitors and VDUs are used to display visual information from computers and other electronic devices, allowing users to view text, images, videos, and other graphical content. They come in various types, including CRT (Cathode Ray Tube), LCD (Liquid Crystal Display), LED (Light Emitting Diode), and OLED (Organic Light Emitting Diode) monitors.

Both the statements are correct-

Statement 1: Using the 'Shift + Delete' keyboard keys deletes the file/folder permanently and it is also not available in Recycle Bin.

Statement 2: Windows 10 allows individual user accounts to have unique settings and preferences (such as the desktop background screensaver) for each user.

An array is used to store values in memory. Arrays allow you to store multiple values of the same data type under a single variable name, making it easier to manage and manipulate data in programming. Arrays are commonly used in various programming languages for tasks such as storing collections of data, performing calculations on large sets of values, and iterating through elements to process them. Arrays are not used for deleting values in memory or for output; their primary purpose is to store and organize data.

A plotter is an output device that prints vector graphics on hard copy. Unlike printers, which are designed for raster graphics and text, plotters are specialized devices used to produce high-quality drawings, diagrams, and other vector-based illustrations. Plotters use pens or other drawing tools to create precise lines and shapes on paper, making them particularly useful for applications that require detailed and accurate graphical output, such as architectural and engineering designs.