I find that chatgpt and claude try to give you one answer and sounds mildly to very certain about themselves without giving references.
Perplexity actually gives reference links for each claim it makes, which I find better because I can check it's work and fork off and explore further myself at any point along it's reasoning.
As a definite AI Hater, I find it to be a good middle ground LLM / search engine
"4k" is supposed to be a term for cinema widescreen resolution, but got taken over because it's short and marketable because "4k is 4x as many pixels as 1080p"
What makes it worse is that then 1440p becomes 2k because "it's 2x as many pixels"
The flip flop irks me