Pure science is science done in a laboratory. It is also called natural science. Applied science is also called technology or engineering. It is done outside. In pure science, a biologist might discover a drug that kills a bacteria. In applied science, a physician might find out if that drug cures a patient. In pure science a physicist might discover a new way to make a diode. In applied science an engineer will see if it works in a television set.
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Pure science deals with abstract ideas and facts and applied science tries to find applications for those ideas