If we scrap youtube data and just display the content being scraped. Is it legal or illegal? The same question I want to ask regarding using YouTube API as well. Can anybody please suggest.
Here's their robots.txt: https://www.youtube.com/robots.txt
They aren't very welcoming of scraping which is also why YouTube is inherently difficult to scrape. You can embed data from YouTube no problem. If you do scrape it and embed it just don't make it obvious that you're scraping it.
Otherwise you're fine.