Question

what is acid and its type

Answer 1

a substance with pure chemical properties and having sour taste is called acid.
types of acids:-
1.acetic acid
2.hydrochloric acid
3. Sulfuric acid
4.citric acid 
and many more

Answer 2

An acid is any substance which dissociates into H+(aq) ions in water.

There are two types of acids:
1) Strong Acids - Which dissociate completely into H+ ions.
Eg. Hydrochloric Acid (HCl), Sulphuric Acid (H2SO4)

2) Weak Acids - Which do not dissociate completely into H+ ions.
Eg. Acetic Acid (CH3COOH), Hydroflouric Acid (HF)