Quantities such as distance, time, mass, weight, etc. Particular instances of say Mass are entities like '3 Kg' or '4 milligrams'.

A rating is an evaluation on a numeric scale, such as 1 to 5 stars.

Describes a reservation for travel, dining or an event. Some reservations require tickets. Note: This type is for information about actual reservations, e.g. in confirmation emails or HTML pages with individual confirmations of reservations. For offers of tickets, restaurant reservations, flights, or rental cars, use [Offer](http://schema.org/Offer).

Represents additional information about a relationship or property. For example a Role can be used to say that a 'member' role linking some SportsTeam to a player occurred during a particular time period. Or that a Person's 'actor' role in a Movie was for some particular characterName. Such properties can be attached to a Role entity, which is then associated with the main entities using ordinary properties like 'member' or 'actor'. See also [blog post](https://blog.schema.org/2014/06/16/introducing-role/).

A schedule defines a repeating time period used to describe a regularly occurring [Event](http://schema.org/Event). At a minimum a schedule will specify [repeatFrequency](http://schema.org/repeatFrequency) which describes the interval between occurences of the event. Additional information can be provided to specify the schedule more precisely. This includes identifying the day(s) of the week or month when the recurring event will take place, in addition to its start and end time. Schedules may also have start and end dates to indicate when they are active, e.g. to define a limited calendar of events.

Used to describe a seat, such as a reserved seat in an event reservation.

A Series in schema.org is a group of related items, typically but not necessarily of the same kind. See also [CreativeWorkSeries](http://schema.org/CreativeWorkSeries), [EventSeries](http://schema.org/EventSeries).

A service provided by an organization, e.g. delivery service, print services, etc.

A means for accessing a service, e.g. a government office location, web site, or phone number.

A SpeakableSpecification indicates (typically via [xpath](http://schema.org/xpath) or [cssSelector](http://schema.org/cssSelector)) sections of a document that are highlighted as particularly [speakable](http://schema.org/speakable). Instances of this type are expected to be used primarily as values of the [speakable](http://schema.org/speakable) property.

A StatisticalPopulation is a set of instances of a certain given type that satisfy some set of constraints. The property [populationType](http://schema.org/populationType) is used to specify the type. Any property that can be used on instances of that type can appear on the statistical population. For example, a [StatisticalPopulation](http://schema.org/StatisticalPopulation) representing all [Person](http://schema.org/Person)s with a [homeLocation](http://schema.org/homeLocation) of East Podunk California, would be described by applying the appropriate [homeLocation](http://schema.org/homeLocation) and [populationType](http://schema.org/populationType) properties to a [StatisticalPopulation](http://schema.org/StatisticalPopulation) item that stands for that set of people.The properties [numConstraints](http://schema.org/numConstraints) and [constrainingProperties](http://schema.org/constrainingProperties) are used to specify which of the populations properties are used to specify the population. Note that the sense of "population" used here is the general sense of a statisticalpopulation, and does not imply that the population consists of people. For example, a [populationType](http://schema.org/populationType) of [Event](http://schema.org/Event) or [NewsArticle](http://schema.org/NewsArticle) could be used. See also [Observation](http://schema.org/Observation), and the [data and datasets](https://schema.org/docs/data-and-datasets.html) overview for more details.

Structured values are used when the value of a property has a more complex structure than simply being a textual value or a reference to another thing.

Used to describe a ticket to an event, a flight, a bus ride, etc.

A trip on a commercial train line.

A trip or journey. An itinerary of visits to one or more places.

An online or virtual location for attending events. For example, one may attend an online seminar or educational event. While a virtual location may be used as the location of an event, virtual locations should not be confused with physical locations in the real world.