Agents are generally classified as general, special, or universal. Text writers and students endeavoring in this wise to more or less closely differentiate the powers of the agent, though a person may be spoken of as a general agent, whose authority would be more limited than the usual definition of a general agent would imply, and one who is called a special agent might have authority to act generally, in the particular business in hand, and so a general agency does not always carry with it authority to act in an unqualified manner in reference to the business in hand. Therefore these classifications must be employed with caution, and the valuable use of the same must not be abused.