A plan is typically any procedure used to achieve an objective. It is a set of intended actions, through which one expects to achieve a goal.

Plans can be formal or informal:

• Structured and formal plans, used by multiple people, are more likely to occur in projects, diplomacy, careers, economic development, military campaigns, combat, or in the conduct of other business.
• Informal or ad-hoc plans are created by individuals in all of their pursuits.

The most popular ways to describe plans are by their breadth, time frame, and specificity; however, these planning classifications are not independent of one another. For instance, there is a close relationship between the short-and long-term categories and the strategic and operational categories.

It is common for less formal plans to be created as abstract ideas, and remain in that form as they are maintained and put to use. More formal plans as used for business and military purposes, while initially created with and as an abstract thought, are likely to be written down, drawn up or otherwise stored in a form that is accessible to multiple people across time and space. This allows more reliable collaboration in the execution of the plan

Planning

The term planning implies the working out of sub-components in some degree of elaborate detail. Broader-brush enunciations of objectives may qualify as metaphorical roadmaps. Planning literally just means the creation of a plan; it can be as simple as making a list. It has acquired a technical meaning, however, to cover the area of government legislation and regulations related to the use of resources.

Planning can refer to the planned use of any and all resources, as in the succession of Five-Year Plans through which the government of the Soviet Union sought to develop the country. However, the term is most frequently used in relation to planning for the use of land and related resources, for example in urban planning, transportation planning, and so forth.

Thus, in a governmental context, "planning" without any qualification is most likely to mean the regulation of land use. See also zoning.

Methodology

The discipline of planning has occupied great minds and theoreticians. Concepts such as top-down planning (as opposed to bottom-up planning) reveal similarities with the systems thinking behind the Top-Down Model.

The subject touches such broad fields as psychology, game theory, communications and information theory, which inform the planning methods that people seek to use and refine; as well as logic and science (ie methodological naturalism) which serve as a means of testing different parts of a plan for reliability or consistency.

The specific methods used to create and refine plans depends on who is to make it, who is to put it to use, and what resources are available for the task. The methods used by an individual in their mind or personal organiser, may be very different from the collection of planning techniques found in a corporate board-room, and the planning done by a project manager has different priorities and uses different tools to the planning done by an engineer or industrial designer.