Period

From Wikipedia, the free encyclopedia

Contents 1 Business 2 Education 3 History 4 Performing arts 4.1 Music 5 Philosophy 6 Science 6.1 Biology 6.2 Chemistry 6.3 Electronics 6.4 Mathematics 6.5 Physics 6.5.1 Astronomy 6.5.2 Optics 7 Literature

Period and periodic may refer to:

1. An interval of time that an event, chain of events, instance or happening, takes place within. It is measured between a start point and an end point and generally repeats (which is where the term period came to describe a female's menstrual cycle) or progresses, in a cycle with the end point of one period being the start point of the next.
2. A long complicated sentence, common in Latin writing and formerly often used in English writing.
3. A full stop, a punctuation mark which indicates the end of a sentence (.).

[edit] Business

• In business, particularly accounting, a period is the time interval(s) that the accounts, statement, payments, or other calculations cover. They won the situation. e.g. Payments, Receipts, Taxes - annually, quarterly or monthly. Salary or wages - monthly, fortnightly or weekly.

[edit] Education

• In schools, a period is the time allocated in the school timetable for instruction in a particular subject.

[edit] History

• Historical period

[edit] Performing arts

• Period piece

[edit] Music

• Period (music)

[edit] Philosophy

• Periodic sentence

[edit] Science

• Periodisation, is the attempt to categorise or divide time, or history, into discrete named blocks.

[edit] Biology

• Menstruation, which usually occurs for discrete periods of time in mammals
• Gene for circadian rhythm

[edit] Chemistry

• Periodic acid. The name is not derived from period, but from iodine: per-iodic acid.
• Periodic table, a table of the chemical elements arranged based on their chemical and physical similarities and differences.
• Periodic table period, which is a row of elements in the periodic table.

[edit] Electronics

• Time between recurring edges of a clock signal. Measured in seconds. 1 / period = frequency.

[edit] Mathematics

• Periodic function, in mathematics and electronics
• Simple harmonic motion
  • Doubly-periodic function
• Periodic point
  • Periodic points of complex quadratic mappings
• Recurring decimal
• Periodic group
• In a group, the period of an element a is the smallest integer n such that aⁿ = e, the identity.
• Periods, a class of numbers

[edit] Physics

• In physics, a period is an interval of time between the recurrence of phases in a vibration, waveform etc.

[edit] Astronomy

• Orbital period, in astronomy

[edit] Optics

• Periodic poling

[edit] Literature

Period is the name of the final novel in Dennis Cooper's George Miles Cycle.