What is the difference between free and paid SMS services?

Free SMS v/s Bulk SMS

Best Free SMS services are:

USAGE:

Free SMS- These services are used by students and the people using SMS services temporarily or just for fun. You can send 50-100 SMS daily through these services.

Best Paid SMS service: 

USAGE:

Bulk SMS- These services are used by business organizations for OTPs, Alerts and also for promoting their businesses. Through these services, you can send LACS of SMS in a single click.