ELI5 Cling Film - what makes it cling?

What makes cling film sticky? Why are there competing theories for how it clings? Why is the Saran Wrap product significantly less sticky today than it was before 2004? Why does wrapping a plastic bag around your credit card help it scan?   ... We explain like i'm five!   Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: 4emonas, jbloom43, genghiskhen, phage0070, meowi_purrr, thirteenera, chippolot, inanecathode, uglydodo, diamondcubeminer, thebladex666, concise_pirate and mattschmie To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: [email protected]