Why does conversion tracking use pixels and why do images potentially provide information about you?

Question

Firstly, why (historically) was conversion tracking implemented using html pixel tracking, using other small and capable of creating almost invisible html elements that could provide the same information? It is curious why html images were used in contrast to other methods.

Secondly, many email clients, for example. Outlook and Gmail do not by default display images in html emails as a means of "protecting your identity." Why do images provide a greater exposure of information than other layout elements on the page? They all appear in some server web log as GET from some IP address with some possible query string lines, so I'm not sure why the images pose an additional risk.

Answer 1

compared to other small and capable of creating-almost invisible html elements that could provide the same information?

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Answer 2

, http- . , .

HTML, . <iframe>, <object>, <script> .

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