Minimum Viable Product (MVP)
Just enough features for the product to work.
Just enough for the first users to accept the product.
Something quite plain, but tangible and allowing users the interaction.
MVP is the product supposed to enable collecting customer feedback for validated learning with the least development effort possible. Based on the previous the product should provide just enough features to be usable which potentially allows to avoid unnecessary work and iterate on working versions that can be tested directly in the market.