It's computer static protection.
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Because the notebook is thin and light, it is often moved around and easy to generate static electricity. The current stored in the notebook itself, coupled with the static electricity of the human body, is likely to cause harm to the notebook, the light keyboard and mouse failure, the black screen of death, the heavy can instantly destroy the laptop - the human body can reach tens of thousands of volts of instantaneous electricity. The integrated circuit in the notebook is extremely sensitive to the phenomenon of electrostatic release, and the strong high voltage released by static electricity in the instant is likely to break down the oxide film inside the integrated circuit, and even burn the circuit in serious cases, with unimaginable consequences.