The term Western world, the West or the Occident (Latin occidens -sunset, -west, as distinct from the Orient) can have multiple meanings dependent on its context (e.g., the time period, or the social situation). Accordingly, the basic definition of what constitutes the West will vary, expanding and contracting, in relation to various circumstances. The historic West originated in the Mediterranean (ancient Greece and ancient Rome), but it came to include Central and Western Europe, although does include the whole of Europe as well as all of Russia (except during the U.S.S.R. era when considered part of the East). Linguistically the frontier would run as far as the Indian Subcontinent. Since Columbus the notion of the West has expanded to include the Americas, through much of Latin America's more pre-Western cultural influence.
As well Australia, New Zealand, the Philippines and South Africa are cultural hubs due to colonization. However during the Cold War the core of the West was often confined to N.A.T.O. countries. Today, in a political or economic context, perhaps the West would also include developed and fast developing countries such as Japan, Taiwan, India and South Korea, etc. In a world religious context, some would include those faiths acknowledging Abraham, however this umbrella's Islamic countries into the category as well. Western society has survived and evolved due greatly to the efforts of the Greeks, Romans, more recently the European empires, and more notably the British Empire. Generally speaking, the current consensus would locate the West in, at the very least, the cultures and peoples of the mainlands Europe, the two Americas, Australia, and New Zealand.
