There are many differences between white hat and black hat seo but when I think of whitehat seo I think of on-page seo, manual link building and promotion on social media via appropriate accounts.
I think of blackhat seo as programmatically blasting out thousands of backlinks or building out thousands of accounts on Facebook, Google, TikTok and the like for purposes of promotion.
There are also other activities that would be considered blackhat but we are not allowed to talk about them on BHW.
I am sure others will give other examples.