Postgraduate Online

Undergraduate courses are courses you take in your first 4 years of college to get your undergraduate degree (BS, BA). These include both general college and those classes in your major. Postgraduate courses are those classes you take to obtain a Masters degree. You need an undergrad degree (thus post, or after, graduation) and admission to grad school to take these classes. Some schools have 5-year masters programs. They are a gift because if you stop school and go back it usually takes an extra 2 years full time to get. You obtain a higher degree (Masters). You can also continue higher education to a Doctorate degree, also post-graduate classes, which will take a couple of years longer in school. The degrees build. Of course, a Masters degree makes you more qualified in your field. And a Doctorate enables you to teach at a college level! Hope that helps you understand.
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undergraduate=when u start college
postgraduate=after college
postgradruate=moremula
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logic

You generally have to do an undergraduate course before doing a postgraduate course. A postgraduate course is usually much more in depth study in a particular area. A postgraduate degree is a higher level qualification than an undergraduate degree.
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Undergraduate degrees are a basic introduction to a subject. They take around 3-4 years to complete and tend to be very broad in their knowledge base. These are generally a Bachelor degree

Postgraduate courses are commenced after you complete an undergraduate degree. They tend to be more focussed, giving you a speciality within your field (which is generally determined by the studies you did as an undergraduate). Post graduate courses are at a higher level than undergraduate courses, and include Masters and PhD level studies, as well as postgraduate certificates and diplomas, which are usually a professional specialist qualification (such as a Postgraduate Certificate in Intensive Care Nursing following a Bachelor of Nursing)

The third main type of course is called a Graduate Course. This is a course completed at a Bachelor level, but requires you to have already completed a Bachelor level course. These courses tend to be fast-tracked, since you have learned how to access information (probably the most important thing your first degree teaches you) and you may already have a basic understanding of the subject matter, depending on what your first degree was.
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Have an undergraduate and graduate degree and am working towards a postgraduate qualification now.