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# CMLogItem

The base class for all motion-related data objects.

```
class CMLogItem
```

## Overview

The `CMLogItem` class defines a read-only [`timestamp`](/documentation/CoreMotion/CMLogItem/timestamp) property that records the time a motion-event measurement was taken.

## Topics

### Getting the Time of the Event

[`timestamp`](/documentation/CoreMotion/CMLogItem/timestamp)

The time when the logged item is valid.

## Relationships

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

### Conforms To

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`CVarArg`](/documentation/Swift/CVarArg)

[`NSCoding`](/documentation/Foundation/NSCoding)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

### Inherited By

[`CMAbsoluteAltitudeData`](/documentation/CoreMotion/CMAbsoluteAltitudeData)

[`CMAmbientPressureData`](/documentation/CoreMotion/CMAmbientPressureData)

[`CMHighFrequencyHeartRateData`](/documentation/CoreMotion/CMHighFrequencyHeartRateData)

[`CMGyroData`](/documentation/CoreMotion/CMGyroData)

[`CMAccelerometerData`](/documentation/CoreMotion/CMAccelerometerData)

[`CMMotionActivity`](/documentation/CoreMotion/CMMotionActivity)

[`CMRotationRateData`](/documentation/CoreMotion/CMRotationRateData)

[`CMMagnetometerData`](/documentation/CoreMotion/CMMagnetometerData)

[`CMDeviceMotion`](/documentation/CoreMotion/CMDeviceMotion)

[`CMAltitudeData`](/documentation/CoreMotion/CMAltitudeData)

---

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