Your disposal can jam if something solid, tough or stringy gets lodged between the spinning plate and the inside wall of the disposal.
There aren't many parts of your garbage disposal that you can or should service yourself, so be sure to call a service professional for any repairs your disposal may need. Never get your hands near the opening while it is running.
TIP: To reduce odors and freshen your drain smell, try grinding a lemon rind into your disposal.
-- Tips courtesy of HomeAdvisor.com