When you read about games you will come across “vanilla game”. These are called games without any addons, mods or DLCs, or expansion packs.
So when you read about something how to do. You could read something like “yea this could do like… but not in vanilla because this is from DLCS…“. Word “vanilla” isn’t used just in gaming you could use it in any software development.
What is vanilla Minecraft?
That’s a basic game that you download from Minecraft.com which has a base game and this version is played most by players. You could have a question if vanilla Minecraft is the same as Java? And the response is yes, they are the same.
But when you make some changes in the launcher (added mods,…) you can’t be called vanilla Minecraft. If you don’t play vanilla Minecraft there is a Technic launcher where you could add mods to Minecraft.
Vanilla OpenTTD vs FIRS?
When you play OpenTTD you could discover FIRS which changes the vanilla game (industry) to more complex industry. So when you play OpenTTD vanilla you play the base game. And if you play modded OpenTTD or FIRS mode in OpenTTD that’s not vanilla.