Planning
Planning is the process of thinking about the activities required to achieve a desired goal. It involves the creation and maintenance of a plan, such as psychological aspects that require conceptual skills. There are even a couple of tests to measure someone’s capability of planning well. As such, planning is a fundamental property of intelligent behavior. An important further meaning, often just called "planning" is the legal context of permitted building developments.
Policy
A policy is a deliberate system of principles to guide decisions and achieve rational outcomes. A policy is a statement of intent, and is implemented as a procedure or protocol. Policies are generally adopted by a governance body within an organization. Policies can assist in both subjective and objective decision making. Policies to assist in subjective decision making usually assist senior management with decisions that must be based on the relative merits of a number of factors, and as a result are often hard to test objectively, e.g. work-life balance policy. In contrast policies to assist in objective decision making are usually operational in nature and can be objectively tested, e.g. password policy.
Urban Planning
Urban planning is a technical and political process concerned with the development and design of land use in an urban environment, including air, water, and the infrastructure passing into and out of urban areas, such as transportation, communications, and distribution networks. Urban planning deals with physical layout of human settlements. The primary concern is the public welfare, which includes considerations of efficiency, sanitation, protection and use of the environment, as well as effects on social and economic activities. Urban planning is considered an interdisciplinary field that includes social, engineering and design sciences. It is closely related to the field of urban design and some urban planners provide designs for streets, parks, buildings and other urban areas. Urban planning is also referred to as urban and regional planning, regional planning, town planning, city planning, rural planning, urban development or some combination in various areas worldwide.
Policy
In a scheme of policy which is devised for a nation, we should not limit our views to its operation during a single year, or even for a short term of years. We should look at its operation for a considerable time, and in war as well as in peace.
Henry Clay. The Clay Code, or Text-Book of Eloquence, a Collection of Axioms, Apothegms, Sentiments … Gathered from the Public Speeches of Henry Clay, ed. G. Vandenhoff, p. 95 (1844).