This is first of the series of video lectures on the engineering suject "Signals and Systems" delievered by Professor Ahsan Ahmad Ursani on behalf of Osar Foundation.br br هن وڊيو ۾ انجنيئرڱ جي مضمون سگنلس ۽ سرشتا تي ليڪچرن جي سلسلي جو پهريون ليڪچر آهي.