Thanks to Netflix Streaming, I've been watching some random classic Doctor Who stories. One thing that strikes me as different between the modern Who and old Who was that in modern Who, they do an awful lot of running. It's become a sort of running gag that they've referenced in-universe. In the classic Who I've seen, he tends to drive around quite a bit instead. In addition, The Doctor in modern Who is incredibly reliant on his sonic screwdriver, which I often don't see at all in classic Who stories.
Did the Doctor running and the sonic screwdriver get introduced over time in classic Who, or were they both added as part of the modern Who revival?