The following outline is provided as an overview of and topical guide to time:

Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, and into the future. It is a component quantity of various measurements used to sequence events, to compare the duration of events or the intervals between them, and to quantify rates of change of quantities in material reality or in the conscious experience. Time is often referred to as a fourth dimension, along with three spatial dimensions.

Below is a structured list of topics related to time:

What type of thing is time?

Time can be described as all of the following:

Time in history

• History of timekeeping devices
• Time periods

General time concepts

• Arrow of time
• Chronology
• Chronon
• Orders of magnitude
• Spacetime
• Time dilation
• Time in physics
• Time standard

Time management

Time management

• Time discipline

Measuring and keeping track of time

• Calendar
• History of timekeeping devices
• Clock

Perception of time

• Mental chronometry
• Time perception

Philosophy of time

• Philosophy of space and time
• Temporal finitism

Time in religion

• Time cycles
• Wheel of time

Time travel

• Time travel
• Time travel in fiction
• Grandfather paradox

Time organizations

Time publications

Persons influential in time

See also

• Outline of physics

References

External links

• Accurate time vs. PC Clock Difference
• Exploring Time from Planck Time to the lifespan of the universe
• Different systems of measuring time
• Time on In Our Time at the BBC
• Time in the Internet Encyclopedia of Philosophy, by Bradley Dowden.
• Le Poidevin, Robin (Winter 2004). "The Experience and Perception of Time". In Edward N. Zalta (ed.). The Stanford Encyclopedia of Philosophy. Retrieved 9 April 2011.