The truth (Ultimate Reality) is one, Sages call it by different names - there is one God, (Supreme Reality) perceived differently.
Supreme Reality - Brahman has two aspects, transcendent (impersonal) and immanent (personal).
In the impersonal aspect Brahman is without attributes (nirguna Brahman).
In personal aspect (saguna Brahman) the God is creator, preserver and controller of the universe.
Saguna Brahman is worshipped in male and female form.
Hindu Deities represent various perceptions of a one God.
Hindus believe in monotheistic polytheism, rather than polytheism.