Searching a little more about singleton I found some comments for and against using this approach.
I still doubt the utility of instantiating a single instance of a class (and making it global) in a web development scenario, where we should load that object between sessions.
In short, my question would be, what is the advantage or what would make a programmer choose the singleton in a web development scenario, since there is no way to create global objects between sessions. Another approach would be to instantiate a class at the beginning of the session and load it into global variables between pages.
Here in this specific scenario I mean web development using php for example.