A doctoral degree is the highest degree you can obtain and sometimes the most valuable. However, it is very time consuming, taking anywhere from 6 to 8 years to complete depending on the field. Usually you are required to not only complete coursework but a dissertation. A dissertation is a research project that aims to obtain new information that would be valuable to your field of study. Also, like the Master's degree you may be required to complete an internship.
You can obtain financial aid to complete a doctoral program. You can be an assistant, obtain a student loan, or even be eligible for a scholarship. The availability and forms of aid vary by discipline (e.g., those in which faculty conduct research sponsored by large grants are more likely to hire students in exchange for tuition) and by institution. Students in some doctoral programs earn master's degrees "along the way."
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