"date" property?

[alpine pasture]

What does this "data" property mean, I can't find a reference to it anywhere:

{
  "format_version": "1.12",
  "minecraft:recipe_shaped": {
    "description": {
    "identifier": "minecraft:acacia_boat"
    },
    "tags": [ "crafting_table" ],
    "pattern": [
      "#P#",
      "###"
    ],
    "key": {
      "P": {
        "item": "minecraft:wooden_shovel"
      },
      "#": {
        "item": "minecraft:planks",
        "data": 4 <---
      }
    },
    "result": {
      "item": "minecraft:boat",
      "data": 4 <---
    }
  }
}

[vapid nimbus]

https://wiki.bedrock.dev/loot/recipes.html#item-object

For example, a data of 1 on log is a spruce log (I think).

[shell hearth]

Data = Data Value of the block

The same as you run command like this

/setblock ~ ~ ~ stone 4
#        This is data ^

[rigid ledge]

So for the example above the planks With a data value of 4 gives you the acacia boat