# Module `iota::event`
Events module. Defines the iota::event::emit function which
creates and sends a custom MoveEvent as a part of the effects
certificate of the transaction.
Every MoveEvent has the following properties:
- sender
- type signature (T)
- event data (the value of T)
- timestamp (local to a node)
- transaction digest
Example:
```
module my::marketplace {
use iota::event;
/* ... */
struct ItemPurchased has copy, drop {
item_id: ID, buyer: address
}
entry fun buy(/* .... */) {
/* ... */
event::emit(ItemPurchased { item_id: ..., buyer: .... })
}
}
```
- [Function `emit`](#iota_event_emit)
## Function `emit`
Emit a custom Move event, sending the data offchain.
Used for creating custom indexes and tracking onchain
activity in a way that suits a specific application the most.
The type T is the main way to index the event, and can contain
phantom parameters, eg emit(MyEvent<phantom T>).
public fun emit<T: copy, drop>(event: T)
Implementation
public native fun emit<T: copy + drop>(event: T);