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Terms and concepts defined

iolo Labs research terms

0-month:a type of machine state. Specifically, a PC simulated by iolo Labs to represent the typical state of a computer that is either brand-new or recently had its operating system installed. A 0-month PC is also referred to as clean state or zero state.

'X'-[unit of time] PC: a type of machine state, where 'X' is replaced with a certain number. Specifically, a PC simulated by iolo Labs to represent the typical state of a computer that has been used for a certain number of months. The number of months used varies by iolo Labs study.

clogged PC: a computer with unneeded files, errors, and obsolete or corrupted settings that cause one or more of its tracked performance traits to be reduced by at least 25%. See also un-tuned PC.

CPU idle usage: the percentage amount of CPU usage that occurs when a computer is idle. During idle time, a PC may be running desired actions, such as a virus scan, but a consistently high percentage indicates an excessive number of background processes are running and thereby reducing the resources available to the PC. For this reason, iolo Labs uses CPU idle usage as an indicator of PC performance.

machine class : a category of both PC and PC user that is used by iolo Labs for testing performance. Each class is defined based on user qualities (usage behavior and intended use) and machine qualities (operating system and other configuration details). Currently, iolo Labs defines five different machine/user classes; refer to machine class for a detailed explanation of each.

machine state: a category used in iolo Labs testing that is based on simulations of PC at specific ages. iolo Labs defines machine states in order to quantify changes over time. See also 0-month and 'X'-month.

memory availability: the percentage amount of RAM a computer has available. With a shortage of RAM, programs do not have enough resources to function properly and can fail to open, run slower, or frequently crash. For this reason, iolo Labs uses memory availability (RAM rather than virtual memory) as an indicator of PC performance.

performance: how a PC functions in regard to speed, responsiveness, and stability. Performance also has subjective qualities, based both on users and their intended use of the PC. What is perceived as low performance by one person may be perceived as high performance by another; what may be acceptable performance for one use, such as emailing, may be unacceptable for another use, such as online gaming. Defining, designing, and testing quantitative measures of performance are among the key objectives of iolo Labs. See also machine class.

registry errors: faulty, corrupted, or obsolete settings in the registry. Due to the critical role the registry plays in Windows operating system processing, iolo Labs uses the number of registry errors as an indicator of PC performance.

simulations: computer models developed for iolo Labs testing that are based on scientific observation of real PCs obtained from real users, both physical machines and PC snapshots. Simulations use aggregated field observations to reproduce a typical PC at specific machine states and include the average number of installed programs, startup items, registry entries and errors, and many other factors.

startup time: the length of time it takes for a PC to completely start up. iolo Labs measures startup time from when the PC is powered on to when the CPU reaches its minimum average idle state (until the average deviation in CPU usage percentage has stabilized).

tune-up database: a continually updated database of information about hundreds of thousands of program files that is maintained by iolo Labs. A team of researchers evaluate the files, create descriptions of their purpose, and then class them into one of several categories that quantify the files' applicability or relevance in specific scenarios.

tuned PC: a PC that has recently undergone a tune-up. Some iolo Labs testing compares tuned PCs to un-tuned PCs to quantify improvements or reductions in performance.

un-tuned PC: a PC that has not recently undergone a tune-up. Where a PC has been un-tuned for a period of time, it is often also clogged. Some iolo Labs testing compares un-tuned PCs to tuned PCs to quantify improvements or reductions in performance.

General technical terms

ActiveX: an interactive technology used to run programs over the internet; for example, an ActiveX component can scan for viruses using a browser, rather than using an installed program. ActiveX was designed for use with Internet Explorer, but other browsers support ActiveX through the use of plug-ins.

browser helper object: a plug-in that adds additional features to the Internet Explorer browser. While most browser help objects provide useful and wanted features, some can perform malicious activities, such as tracking viewing habits or navigating users to unwanted sites.

CPU (central processing unit): an electrical circuit responsible for most of the data processing done by a computer. The CPU executes instructions from both hardware and software components. The CPU is also referred to as a "processor."

CPU usage: the percentage amount of time the CPU spends processing user applications and high-level Windows functions; low-level functions, such as mouse and keyboard input, do not affect CPU usage. A CPU usage of 100% indicates the processor is fully used; 0% indicates the processor is not being used at all.

crash: a software or hardware error that occurs without warning and causes a computer to stop responding or stop working.

GHz (gigahertz): the common measure of the speed of a computer's CPU. One GHz is equal to one billion cycles per second, which indicates how many instructions per second the processor can execute.

idle: the period when a computer is powered on but is not being used by a person. Note that during idle time, the computer may still be running processes.

MB (megabyte): a standard unit used to measure the storage capacity of a disk and the amount of computer memory. A megabyte is colloquially referred to as a "meg."

operating system: software that controls and manages hardware and basic system operations for a computer. The operating system loads programs into the computer's memory, runs these programs, and manages peripherals like disks and printers.

physical memory: See RAM.

plug-in: a small program that is added onto another program, enabling it to perform additional functions. A browser help object is a commonly seen type of plug-in.

RAM (random access memory): the physical, working memory of a computer where data is temporarily stored for various processes. A higher amount of RAM means there is more space available for temporary data storage, which speeds processing. Note that RAM is physical memory, which differs from virtual memory.

registry: a database that holds configuration settings used by the Windows operating system. The registry is vital to a PC's ability to run correctly—it stores key data that Windows requires and continually references, such as user profiles and settings for installed software and hardware.

registry bloat: a condition in which the size of the registry has grown significantly and has an excessive amount of unused space. Unused space is created when registry values are created or deleted, such as through installations, uninstallations, and registry repairs.

registry compaction: a software-based process designed to eliminate registry bloat. The process can speed registry access and release RAM that was previous needed to store empty registry entries in memory.

registry defragmentation: a software-based process designed to restructure the data in the registry. The process can speed registry access and improve registry efficiency.

registry repair: a software-based process designed to recondition a registry by comparing registry values to installed software and hardware and then correcting or removing any erroneous, outdated, or orphaned entries.

service (or Windows service): an executable that performs specific functions in the background. Typically, services do not require any user intervention and run automatically as part of startup.

startup (or Windows startup): the group of programs and services that Windows loads every time a PC is turned on or restarted. Some of these actions are required and desired, but some may not be needed for a PC's intended use and can needlessly slow the system down.

tune-up (or PC tune-up): a software-based process designed to reverse the degradation of PC performance that occurs with usage. A tune-up can entail many different repairs and optimizations, but it typically includes diagnosing and fixing errors, cleaning out unneeded files, eliminating corrupted or obsolete settings, and adapting system configurations to enhance speed and stability.

virtual memory: memory stored on a hard drive or other removable media that provides extra memory for a computer. Segments of virtual memory are referred to as a "page file" or "swap file." Note that virtual memory differs from physical memory.

Windows (or Microsoft Windows): The operating system developed by Microsoft.