Histogram

This histogram sample shows the frequency distribution of web page load time.
"Web performance optimization, WPO, or website optimization is the field of knowledge about increasing the speed in which web pages are downloaded and displayed on the user's web browser. ...
With the average internet speed now increasing globally, it's fitting for website administrators and "webmasters" to consider the time it takes for websites to render for the visitor.
Faster website download speeds have been shown to increase visitor retention and loyalty and user satisfaction, especially for users with slow internet connections and those on mobile devices. Web performance also leads to less data travelling across the web, which in turn lowers a website's power consumption and environmental impact. Some aspects which can affect the speed of page load include Browser/ Server Cache, Image Optimization and also encryption (for example SSL), which can affect the time it takes for pages to render." [Web performance optimization. Wikipedia]
The histogram example "Page load time" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Histograms solution from the Graphs and Charts area of ConceptDraw Solution Park.