Sometimes you want to do something that an item component alone cannot achieve. So, this is why item events exist! With item events you can act upon something happening to an item yourself. All events and their handlers are found in a list in the events field on an item. Below is a table with all item events and when they occur.

{
  "base": {
    "translation_key": "item.minecraft.milk_bucket"
  },
  // ...
  "events": [
    {
      "event": "minecraft:consume_item",
      "entry": {
        "action": {
          "type": "minecraft:clear_status_effects",
          "entity": "this"
        }
      }
    }
  ]
}