To earn a PhD, students must typically complete coursework and research in a specific field of study. They must also write a dissertation, which is a long research paper that makes an original contribution to the field. The dissertation must be defended before a committee of experts in the field.
The time required to earn a PhD varies from country to country and from university to university. In the United States, it typically takes five to eight years to complete a PhD. In the United Kingdom, it typically takes three to four years.
PhD degrees are highly respected and can lead to many career opportunities. PhD holders may work as professors, researchers, scientists, engineers, and other professionals in a variety of fields.