Generic drugs refer to drugs that have no patent right, or the patent right is terminated for various reasons, or the exclusive right of the patentee to produce and sell the drug disappears, or the technology for producing the drug enters the public domain.
Generic drugs, generic drugs refer to imitations that are the same as the brand name drugs in terms of dosage, safety and strength (no matter how to take them), quality, performance and expected use.
The biggest difference between the two is that the former has no patent. The imitator of the latter may have a patent.