Do I have to create a user ID / calendar purpose

Hello,

I need to create a calendar for a few people in the company. Reminder will be create in this calendar so they will not miss important event. One personne will have the right to create events, others will consult the calendar.

I was wondering if I have to create a user ID for that purpose? (since no e-mail will be used, I do not think I will need it.)

Thanks for your help.