## Pass Issuer

The passes issuer is the entity that owns the pass and is responsible for
issuing passes to their passengers. This could be you, the developer, or the
organization that you represent.

In order to become a passes issuer, you must first register as an Issuer.

## Boarding Pass class

A `FlightClass` can be thought of as scheduled flight. An issuer can
create multiple scheduled flights with permutation of routes and timings. Each
`FlightClass` representing a scheduled flight can contain its own
appearance and data fields to meet the airport-specific requirements.

In addition, a `FlightClass` can also be used to enable additional
features like Smart Tap.

## Boarding Pass object

A Boarding Pass object is an instance of a Boarding Pass class. A new
`FlightObject` instance needs to be created for each passenger that's
distributed with a Boarding Pass.

## Pass Class

A Boarding Pass class is a type of pass class. Pass classes describe general
information for related pass objects (such as style and appearance), and don't
include passenger details.

Other types of pass classes include the following:

- Loyalty cards
- Event tickets
- Gift cards
- Offers
- Transit passes
- COVID cards

## Pass Object

A `FlightObject` is a type of pass object. Like a
`FlightObject`, a Pass Object is an instance of a corresponding pass
Class. A pass object needs to be created for each passenger that's issued a
Boarding Pass.

Pass objects contain passenger-specific information. For example, they can be
used to identify that a passenger not only has a ticket for a flight, but also
identify which seat on the flight they've been allotted.

## Service account

The service account is the identity that's used to call the Google Wallet API.
Permission to access the Google Wallet API needs to be granted to this service
account.

## Service account key

The service account key is the credential used to authenticate your
application as the service account. The service account key is highly sensitive
and needs to be kept private. If a third party has access to the service account
key, they can identify themselves as the service account and perform actions
that the service account is permitted to perform.