Computer Science Test 4 Nddc Scholarship

A companion virus is a clever type of malware that does not actually modify existing files. Instead, it creates a new file with the same name as a legitimate program but with a different extension (for example, creating 'program.com' to accompany 'program.exe'). Because many operating systems prioritize certain extensions, the virus executes first when the user tries to run the legitimate application.

A packet sniffer (also known as a network analyzer) captures and inspects data packets as they travel across a network. While essential for network troubleshooting and monitoring, it can be used maliciously to 'eavesdrop' on a network. If data like passwords or emails are sent in 'clear text' (unencrypted), the sniffer can easily read that sensitive information.

In common security terms, a hacker is an individual who uses their technical expertise to bypass security measures and gain unauthorized access to data or systems. While the term can refer to any skilled programmer, in a security context, it specifically describes someone performing illegal intrusions into networks to steal information or cause disruption.

The Encrypting File System (EFS) is a feature of the Windows NTFS file system that provides file-level encryption. It allows users to encrypt individual files or entire folders so that even if an unauthorized person gains physical access to the hard drive, they cannot read the contents of the files without the correct cryptographic key or user login.

Logging on (or logging in) is the fundamental security procedure used to verify a user's identity. By providing a unique username and a secret password, the system can authenticate the user and grant them specific permissions to access files and applications based on their assigned security profile within the operating system or network.

Intrusion detection refers to the monitoring of computer systems or networks for signs of security violations or unauthorized activity. It involves analyzing traffic patterns and system logs to identify 'anomalies'—behavior that deviates from the norm—that might indicate a hacker is attempting to break in or that an internal user is misusing their privileges.

In Windows 3.x, cooperative multitasking was the standard method for managing 16-bit applications. In this mode, the operating system relies on the applications themselves to voluntarily release control of the CPU so that other programs can run. If a single application stops responding or refuses to 'yield,' it can effectively freeze the entire operating system until that process is terminated.

Laser printing is an electro-photographic process where a laser beam creates an electrostatic image on a light-sensitive drum. Static electricity then attracts powdered ink (toner) to the charged areas of the drum. Finally, the toner is transferred to paper and fused permanently using heat and pressure from a fuser assembly.

A Disk Boot Failure indicates that the BIOS could not find a valid operating system to load. This typically happens because the hard drive's system boot files are missing or corrupted. To resolve this, you generally need to boot from a recovery disk and repair or replace the essential startup files on the primary hard drive to restore normal operation.

The FORMAT command in DOS is used to prepare a disk for data storage. When used with specific parameters (like /S), it not only structures the disk but also copies the hidden system files necessary for the computer to use that disk as a bootable device. This allows the computer to load the DOS kernel directly from that disk upon startup.