FIT stands for Free Independent Travelers (or Tourists).

 It means a small number of tourists (usually fewer than 5 persons
 or couples) who take packaged tours at a time of their own choice.

 GIT stands for Group Inclusive Tour.

 It is a travel program with a special fare and specific requirements
 (usually a minimum number of persons often more than 5 persons
 traveling as a group throughout the tour).