The caged bird sings while he is locked in a cage. His wings are clipped and legs are tied. He can seldom see through the ‘bars of rage’. 
 
The bird is essentially deprived of freedom, rights and justice. He is fearful with the utmost uncertainty of his life. He has never experienced freedom and so doesn’t even know how it tastes. Locked in the cage, he is both saddened and angry at the same time. Sometimes, he is hopeful too. He hopes to get what the free birds are enjoying someday and so he opens up his throat to sing of freedom.