The EFF has a very  informative article on corporate surveillance in
all its forms  - on the web  and in real life [0][1].  It's long but
well worth reading.  A lot of it won't  be new to many of  us on the
small internet, at least in concept.  I was certainly aware that all
these forms of tracking existed, but I learned things I did not know
about how the various methods work  and the lengths the data brokers
will go to tie behavioral data to a real person.

[0] https://www.eff.org/wp/behind-the-one-way-mirror
[1] gopher://republic.circumlunar.space/1/~slugmax/articles/eff-corporate-surveillance