The phrase "rudimentary form" refers to something that is basic, simple, or in its early stages of development. It means that an object, concept, or idea is only just beginning or lacks complexity and sophistication. Full definition
You have to rely on each other's goodwill, with only very rudimentary forms of communication. (theguardian.com)
Today, we know by experience (DNA technology) that all the human organisms are present in rudimentary form in the human embryo, and that there is no essential change from conception to adulthood. (faith.org.uk)
Currently, No Man's Sky has a very rudimentary form of multiplayer that represents other players as glowing orbs and doesn't offer much direct interaction beyond voice chat. (gamecrate.com)