Related Lists in the contact record
Like all Salesforce Records - Contacts have related lists of objects that a contact is related to via lookup fields on other objects.
The related lists in your instance of Salesforce may vary from those pictured here as these are customizable by your system administrator.
The following related lists appear in the contact record saved view
Connections - A list of all connections between this volunteer and the opportunities/occurrences they have signed up for
Volunteer Team Members - a list of all teams where they are a member or a captain with a summary of hours served as part of that team.
Skill Ratings - details from their volunteer skill profile
Registration Answers - Answers to any custom questions that you have added to the standard registration form. (Custom questions can be added by your system administrator).
Open Activities - any tasks or events you schedule with this contact
Activity History - a historical record of past activities. You can also use the buttons here to Log a call, Send an Email, or Request an update (a stock email asking for a review of contact information)
HTML Email Status - a record of emails sent in the past. The "Send an Email" button allows you to send an email to the contact. (From here you can use email templates that you have created in your personal setup).
Notes and Attachments - you can attach notes or files to the contact record here. (Note: notes marked as 'private' are accessible to you and any system administrator - so they are not completely private.)
Related Lists in SF Lightning
If you are using SF lightning related lists are presented in a number of different ways. You may have a "related list quick links" component - that gives access to each related list, or you can always click on the Related Tab in the page layout: