What is the difference between conversion and micro-conversion?

Conversion (the completion of a goal desired from the site owner's perspective) can be split by the level of business goals. The main e-commerce goal is the transaction, while a micro-conversion can be a newsletter signup, adding a product to the cart, or starting a chat with a consultant on the site. Measuring micro-conversions in e-commerce is justified for several reasons:

they help us understand customer behavior on the site better: they reflect what stage of the funnel users are at — people who already added a product to the cart are usually closer to a transaction than those who were on the site briefly without any interaction,

they can simplify campaign optimization in Google or Facebook: when it's hard to reach the minimum conversion volume that helps ad systems optimize, it's worth using interactions that signal a higher likelihood of conversion and that can be collected in much greater numbers in a much shorter time.

we can better identify optimization opportunities on our store: measuring more than just the purchase helps answer the question of how users who bought differ from those who haven't yet.