What is the difference between Transactional and Promotional SMS/route?

Transactional VS. Promotional

Following are the listed differences between Transactional and Promotional routes:

Transactional Promotional
1.  These can be used for
      sending any type of information. 
      Ex. OTP, Bank Transactions etc.
1.  These are specifically used for
      marketing purposes.
      Ex. Sale, offers etc.
2.  Transactional SMS
     can be sent any time
2.  Promotional SMS are sent
      between 9 am to 9 pm only
3.  SMS can be sent on DND numbers  3.  SMS cannot be sent on DND numbers 
4.  In API route=4 4.  In API route=1