Ideas are not intellectual property and can't be protected.
Exists automatically when an artistic or literary work is fixed in a tangible form. "Artistic" and "literary" are interpreted broadly so an architect's plans are protected as is computer code.
Only the specific expression and any derivative work is protected. If I want to write a novel about children being taken to a school for magic I am not breaching anyone's copyright so long as my work is not derived from any work that may be pre-existing.
Protects product identity: names, logos, colors, sounds etc. that are associated with a particular range of goods or services - Micky Mouse's ears, Intel's "ting", Apple's logo as well as the names of those products are all trade marks.
Trade marks can either arise through usage or registration and are limited to the jurisdiction and market they are used/registered in.
Trade marks must continue to be used and can be lost through disuse. Less commonly, they can also be lost through genericization - asprin, linoleum, escalator and trampoline were all once trade marks.
A patent must be registered and protects an invention. This is more than an idea - the patent must be something that can be built/used by anyone reading the patent (assuming they have the skills/resources - nuclear reactors are not easy to build even if you have the instructions).
The information provided to gain the patent is made public but the patent holder has exclusive rights to its use for a period of time.
Registered Design or Design Patent or Community Design
By whatever name, these protect the "look" of a physical object like a car or a chair - unlike a patent, they do not have to be inventive or original. While the plans of say, a chair, are protected by copyright - the chair itself isn't because its a functional object - not artistic or literary. This is what these protect. They must be applied for.