Legacy Glossary

This is a glossary of older terms. While many of the definitions are unchanged, some of the definitions may be out of date and some of the terms may no longer be in use in the Data Center industry. This legacy glossary provides definitions for hundreds of information and communications technology (ICT) and data center terms and acronyms. Arranged alphabetically and searchable, the glossary explains common industry vocabulary.
1 A B C D E F G H I K L M N O P R S T U V W Z

Formerly, the Institute of Electrical and Electronics Engineers, Inc.


Flow of outdoor air into a building through cracks and other unintentional openings and through the normal use of exterior doors for entrance and egress. Also known as air leakage into a building


A class of arithmetic, commonly used in computers. Integer arithmetic deals only in whole numbers, e.g., 1, 2, 99, 4563. Any calculation that does not result in a nice whole number is truncated back to a nice whole number and the fractional part is thrown away, e.g., 9/4 = 2 and not 2.25 or two and a quarter. Typically, computers can perform integer arithmetic more quickly than they can any other form of arithmetic, so most programs do as much work as they can in integer. However, most computers have significant limits on the values they can manage in integer format. Besides the lack of fractions, many computers cannot handle integer values beyond the millions. Thus, integers can be used to count time or to keep track of all the pennies in your bank account. However, most scientific applications deal with large values or need to be more precise than just throwing away the fractions. These kind of applications then make use of floating point arithmetic. For the SPEC CPU benchmarks, applications are classified as "integer" if they spend less than 1% of their time performing floating point calculations (which covers most non-scientific applications, e.g., compilers, utilities, simulators, etc.

International Electrotechnical Commission (IEC)

A global organization that prepares and publishes international standards for all electrical, electronic, and related technologies

Iron Whiskers

See whiskers, iron


International Organization for Standardization


Information technology


Information technology equipment


International technology roadmap for semiconductors