BAD : The whole world watched the cup final on televisions.
GOOD : The whole world watched the cup final on television.
Television (also TV ) is usually uncountable: 'The children watch a lot of television.' 'The article explains how television affects family life.'
As a countable noun it means 'a television set': 'Some parents buy two televisions - one for the children to watch and one for themselves.'
BAD : Cigarettes are no longer advertised in television.
GOOD : Cigarettes are no longer advertised on television.
See note at RADIO (↑ radio )