Click on the "Customize" command in the blue command bar to find the Share With controls for your calendar.

If you want others to be able to view your calendar without them needing their own KeepandShare accounts, share your calendar with 'Public' by clicking a Group and choosing 'Public', and then click on the blue 'Update' button:

If you want private sharing, just type in the KeepandShare user name you want to share with, such as "JSmith" into Usernames and then click on Update (Note: you cannot put email addresses into the Share With fields, your friends will need to have KeepandShare user accounts, use Invite a Friend to easily create accounts for them).

When you share a calendar, other users can view the calendar. Click on the "edit" checkbox next to each field if you want to grant them edit rights.

If you want to share a calendar with more than two users, you should first create a share group. Share groups can include unlimited number of users, and can be used again and again to share many documents, photo blogs and other KeepandShare information. In the following image you can see this user has defined a number of share groups and has just selected "A Team".

If you maintain multiple calendars (e.g., one for work and one for home), each one can have separate sharing settings.