Expertise and Talent are two words that are often confused as words that give the same sense although they are not so. They in fact show some differences when it comes to their connotations. Expertise means thorough knowledge in any given field. On the other hand talent is the ability to execute work.
A person endowed with talent need not be possessed with expertise in the particular field of work. For example a person who is endowed with the gift of voice has the talent of singing but he not be bestowed with the expertise of the art of music. He may not know the nuances of music and musicology.
Another important difference between expertise and talent is that expertise grows by experience whereas talent gets exposed on its own. A manager of a firm gains expertise in the branch of marketing by experience. On the other hand a young salesman can have the talent of generating sales not based on his experience in the field but simply by virtue of his communication skills and ability to impress upon the customers. A young salesman who is adept in making sales need not have an expertise in the field of marketing.
A person who is endowed with talent in any field need not be bestowed with expertise in the field. There is no steadfast rule that he should be endowed with a deep knowledge in the particular subject or field. Everything comes naturally to a person who has talent.
On the other hand a person who gains expertise does it with years of hard work and learning. In other words high learning accompanies expertise whereas deep learning need not accompany talent. It is generally believed that talent is God-given whereas expertise is hard-earned. It has to be earned thorough research and performance in the particular field.