Loading speed, web and servers
HAR
Abbreviation for HTTP Archive
In short and in plain language
HAR is a file in which the browser records how a page loads.
It lists every request with its times. So you can pass the recording on to others.
The file may also hold login data. So you should clean it up first.
Definition
HAR is a file format in which browsers save the requests made while a page loads, including timings and headers. Such a recording can be shared and opened in other tools, for example to review a waterfall chart together. It may contain cookies and login data, so it should be sanitized before it is shared.