types of antenna

directional (monodirectional, bidirectional, and multidirectional)
omnidirectional (falsely called as, non-directional*)

there is no non-directional antt as such. 
each antt points in some or the other direction. 
antts. ranges from 'atleast in one direction' to 'atmost in all directions'

mono-source (point-source or single-element-antt.**)
multi-source (array-of-point-source or multielement-antt.**)

if it is non-directional, it must be having a single element antt.
if it is directional, it must be having an array of point source

active antt: transmitting antt or transmitter (or, radiator)
passive antt: receiving antt or receiver

naturally, antt not only radiates, but also receives. 
it radiates as per the received info. and receives as per the radiated info. its like reflex mechanism of a living body (respond to a stimulus and stimuli to a response)


hi-directivity antt. (long distance comm. antt.)
lo-directivity antt. (short distance comm. antt.)