in the meaning both are same booking and reservation
but mostly reservation used for the train related . where you reserve the seat in advance
booking terms used for the ticket booking or any service booking or taxi booking
suppose like below statement
1. Archirayan infotech provide you best taxi booking app
we can use taxi reservation app instead of taxi booking
2. Archirayan infotech is market lead in Flight booking website development
3. Archirayan infotech has team which make train reservation online service app and website
etc..
Hope it clear
www . archirayan . com