Key difference: Independent and dependent are antonyms. Dependent is when someone does have to rely on somebody else, whereas independent is when one does not have to rely on anybody.

Independent and dependent are two terms that are actually antonyms. Essentially, that means that they are opposites.

Dictionary.com defines Independent as:

• Not influenced or controlled by others in matters of opinion, conduct, etc.; thinking or acting for oneself: an independent thinker.
• Not subject to another's authority or jurisdiction; autonomous; free: an independent businessman.
• Not influenced by the thought or action of others: independent research.
• Not dependent; not depending or contingent upon something else for existence, operation, etc.
• Not relying on another or others for aid or support.
• Rejecting others' aid or support; refusing to be under obligation to others.
• Possessing a competency: to be financially independent.
• Sufficient to support a person without his having to work: an independent income.
• Executed or originating outside a given unit, agency, business, etc.; external: an independent inquiry.
• Working for oneself or for a small, privately owned business.
• Expressive of a spirit of independence; self-confident; unconstrained: a free and independent citizen.

Whereas, Dependent is defined as:

• Relying on someone or something else for aid, support, etc.
• Conditioned or determined by something else; contingent: Our trip is dependent on the weather.
• Subordinate; subject: a dependent territory.

Essentially, independent is when one does not have to rely on something or somebody, It is when they only rely on themselves. Dependent, on the other hand, is when someone does have to rely on somebody else. They may not be able to get by without whatever or whoever they are dependent on.

Let us consider an example:

A child is dependent on his mother for food and care. If the mother is not there, then the child cannot fend for himself, or provide for himself. However, the mother is independent because she can fend for herself and feed herself. She is not dependent on anyone.

A patient is dependent on the medication to feel better, without the medication, the patient will not get better or may even get worse. However, a healthy person is not dependent on a particular medication; hence he is independent.

The term, independent may also refer to somebody who is different from everybody else. His thoughts, beliefs, and actions are not dependent on everybody else’s thoughts, beliefs, and actions. He does not cater to the herd mentality; he stands apart. He thinks and acts for himself. 

Image Courtesy: franthony.com, nickandzuzu.com