Idealism

Idealism is a philosophy which states that reality is either mentally constructed or immaterial. Idealism also states that consciousness exists before the material existence.

Subjective and Objective Idealism
Subjective Idealism, also known as/related with Immaterialism and Phenomenalism, states that the individual know sensations and ideas, rather than abstractions (such as matter).

Objective Idealism states that the reality of experiences is combined with the reality of the experienced object and the mind of the observer.