To access these filters:

From the Navigation Toolbar on the left, click Contacts and select View Contacts.
At the top-left, you should see a view name called All Active Contacts or Marketing Contacts.
Click the view name to access the filters.
Click a different filter to go to that view.
This
filter displays the list of all the active contacts in your account.
Active contacts includes contacts from marketing and non-marketing
filters. These are the contacts whom you engage with on a regular basis
by sending them marketing campaigns like email campaigns. Contacts that
are unsubscribed, bounced, blocked, and invalid aren't considered active
contacts.
Marketing
As the name states, this filter displays all the contacts whose subscription type is Marketing. You'll mainly engage with these contacts for your marketing needs. Non-marketing
This filter lists all the contacts whose subscription type is Non-marketing. These contacts haven't provided you with permission to engage with them.
Unsubscribed (Marked by Recipient)
This
filter shows the contacts who've unsubscribed of their own accord from
your marketing emails, campaigns, and SMSs via the unsubscribe link
provided. Their subscription type is Unsubscribed.
Unsubscribed (Marked by Sender)
This
filter lists the contacts who've been unsubscribed by you or other
users of your Zoho Marketing Automation account. They could've been
marked as unsubscribed while creating a new contact, via import, bulk
update, or via journeys. Their subscription type is Unsubscribed.
Bounced
This filter lists the contacts whose email addresses have suffered bounces. An email address can be bounced for a variety of reasons, such as: Recipient email address does not exist.
Domain name does not exist.
Typos render the email address invalid. (For example, gnail.com instead of gmail.com)
Recipient email server has blocked delivery.
The email address is inactive.
The email account has been closed.
Only
the contacts whose email addresses have suffered hard bounces will be
listed in this view. If an email address has soft bounced, there are
chances for the email to get delivered to that address in the subsequent
retries. Hence, soft bounced email addresses won't be listed. Learn
more about hard and soft bounces here. Blocked
This
filter is used only when a Zoho Marketing Automation user requests we
block contacts whose email addresses are of a particular domain so
existing contacts are blocked and future contacts of this domain don't
get added.
Invalid
Whenever
you create a contact in Zoho Marketing Automation, the system will do a
real-time validation of the email address to see if it is valid or not.
If it's an invalid email address, the system will flag it so you can't
save the contact unless a valid email address is provided.
However,
there are instances where the validity check gets bypassed and the
contacts get added. It can be via a sync from a different Zoho
application such as Zoho CRM, via import, or — very rarely — when
you manually add a contact. In such cases, the system will do a check
after the addition of these contacts and move them to the Invalid view automatically.
Setting a view as the default
Set a view of your choice as the default, so each time you go into the View Contacts module, this view always appears:
From the Navigation Toolbar on the left, click Contacts and select View Contacts.
At the top-left, click the specific view name to access the list of filters.
Hover over the desired filter and click the more actions button (the three vertical dots).
Click on Set as default view.