Digitals

Ladies can you clear up something for. Me. I've been told and I remember from The past that digitals will ALWAYS have 2 or 3 lines. I have encountered people on here and friends that have taken digitals in the past taken them apart and have only one line ...so can it be clarified if it's based on the brand maybe? ? From what I understand all digitals have more than 1 line but from friends and people one here that's false??