# TimeData

> Encapsulates state to measure a World 's simulation time.

## Definition

* **Type:** Struct
* **Namespace:** [Unity.Core](/engine/7000.0/script-reference/unity/core.md)
* **Assembly:** UnityEngine.EntitiesModule

```csharp
public readonly struct TimeData
```

## Remarks

This data is most frequently read using Time. It is updated every frame by UpdateWorldTimeSystem. To temporarily override the time values, use [World.SetTime](/engine/7000.0/script-reference/unity/entities/world/settime.md) or [World.PushTime](/engine/7000.0/script-reference/unity/entities/world/pushtime.md).

## Fields

| Value                                                                             | Description                                                                              |
| --------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| [DeltaTime](/engine/7000.0/script-reference/unity/core/timedata/deltatime.md)     | The time in seconds since the last time-updating event occurred. (For example, a frame.) |
| [ElapsedTime](/engine/7000.0/script-reference/unity/core/timedata/elapsedtime.md) | The total cumulative elapsed time in seconds.                                            |

## Constructors

| Constructor                                                                                          | Description                                         |
| ---------------------------------------------------------------------------------------------------- | --------------------------------------------------- |
| [TimeData(System.Double,System.Single)](/engine/7000.0/script-reference/unity/core/timedata/ctor.md) | Create a new TimeData struct with the given values. |

## Properties

| Property                                                                                | Description                                                                                                       |
| --------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------- |
| [fixedDeltaTime](/engine/7000.0/script-reference/unity/core/timedata/fixeddeltatime.md) | Currently, an alias to [Time.fixedDeltaTime](/engine/7000.0/script-reference/unityengine/time/fixeddeltatime.md). |