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docs/recipes/dive-into-event.md

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+# Dive Into Events
+
+The events recorded by rrweb are a set of strictly-typed JSON data. You may discover some flexible ways to use them when you are familiar with the details.
+
+## Data Types
+
+Every event has a `timestamp` attribute to record the time it was emitted.
+
+There is also a `type` attribute indicates the event's type, the semantic of event's type is:
+
+```
+type -> EventType.DomContentLoaded
+event -> domContentLoadedEvent
+
+type = EventType.Load
+event -> loadedEvent
+
+type -> EventType.FullSnapshot
+event -> fullSnapshotEvent
+
+type -> EventType.IncrementalSnapshot
+event -> incrementalSnapshotEvent
+
+type -> EventType.Meta
+event -> metaEvent
+
+type -> EventType.Custom
+event -> customEvent
+```
+
+The EventType is Typescript's numeric enum, which is a self-increased number from 0 in runtime. You can find its definition in this [list](https://github.com/rrweb-io/rrweb/blob/9488deb6d54a5f04350c063d942da5e96ab74075/src/types.ts#L10).
+
+In these kinds of events, the incrementalSnapshotEvent is the event that contains incremental data. You can use `event.data.source` to find which kind of incremental data it belongs to:
+
+```
+source -> IncrementalSource.Mutation
+data -> mutationData
+
+source -> IncrementalSource.MouseMove
+data -> mousemoveData
+
+source -> IncrementalSource.MouseInteraction
+data -> mouseInteractionData
+
+source -> IncrementalSource.Scroll
+data -> scrollData
+
+source -> IncrementalSource.ViewportResize
+data -> viewportResizeData
+
+source -> IncrementalSource.Input
+data -> inputData
+
+source -> IncrementalSource.TouchMove
+data -> mouseInteractionData
+
+source -> IncrementalSource.MediaInteraction
+data -> mediaInteractionData
+
+source -> IncrementalSource.StyleSheetRule
+data -> styleSheetRuleData
+
+source -> IncrementalSource.CanvasMutation
+data -> canvasMutationData
+
+source -> IncrementalSource.Font
+data -> fontData
+```
+
+enum IncrementalSource's definition can be found in this [list](https://github.com/rrweb-io/rrweb/blob/master/src/types.ts#L64).