What goes in the Common Interface slot on the TV

What is the purpose of a Ci slot on a TV? ci plus slot BMW OEM CI Plus TV Card Module 8792114 65128792114 G20 F90 M5 G30 G32 GT G11 G14 Pre-owned £ Free postage · Technisat CI-SLOT for Skystar ci slot Being mandated by a European Directive, CI Plus slots are present in basically all TV sets sold in Europe DVB has, since 2014, published extensions to CI Plus

cinta slot BMW OEM CI Plus TV Card Module 8792114 65128792114 G20 F90 M5 G30 G32 GT G11 G14 Pre-owned £ Free postage · Technisat CI-SLOT for Skystar