User interacts with a Browser and types a url or clicks a link or fills a form and the Browser sends a http/html request to a Web Server,and a Web Server sends back a http/html response to Browser.(HTML is language that browser understands).
Then users views the html response.
If we are using JMeter then user and browser is not required.All we need is the html request.So we use samplers in Jmeter
for these requests.Web servers sends back the reponse for Jmeter Sampler request.We can interpret the response using listeners.
If loop count is 10 then 10 such requests are sent for each user.