How does smoking weed get you high?

As stated above the plant itself doesnt get you high, the THC "Tetrahydracannibinoid" the compound in the female marijuana plant buds that bind to you brains neurotransmitters releasing serotonin and dopamine is the high you feel. Drugs of any type does not make a person feel high, it the sudden release of the pleasure chemicals in the human brain, (dopamine, seratonin, ect.)  The drug causes the brain to release large quantities of these at once,  creating the euphoria, that people call "a high"