demonstration

a show or display; the act of presenting something to sight or view; "the presentation of new data"; "he gave the customer a demonstration"

a show of military force or preparedness; "he confused the enemy with feints and demonstrations"

a public display of group feelings (usually of a political nature); "there were violent demonstrations against the war"

proof by a process of argument or a series of proposition proving an asserted conclusion

a visual presentation showing how something works; "the lecture was accompanied by dramatic demonstrations"; "the lecturer shot off a pistol as a demonstration of the startle response"