This video here explains some possible ways of the extinction of humans.

In futures studies, human extinction is the hypothetical end of the human species. This may result from natural causes or it may be the result of human action. The likelihood of human extinction in the future by wholly natural scenarios, such as a meteorite impact or large-scale volcanism, is generally considered to be extremely low.
For anthropogenic extinction, many possible scenarios have been proposed: human global nuclear annihilation, biological warfare or the release of a pandemic-causing agent, overpopulation, ecological collapse, and climate change; in addition, emerging technologies could bring about new extinction scenarios, such as advanced artificial intelligence, biotechnology or self-replicating nanobots. The probability of anthropogenic human extinction within the next hundred years is the topic of an active debate.
Human extinction needs to be differentiated from the extinction of all life on Earth (see also future of Earth) and from the extinction of major components of human culture (e.g., through a global catastrophe leaving only small, scattered human populations, which might evolve in isolation).

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