best practices when using several plugins

best practices when using several plugins

Hi, I'm trying to understand the best practices to add my jquery plugins in my code.

For example, I've seen people that when using three or four of them they would add them right before body tag closes. I would like to know why is better this way.

Also would like to know if you should take all plugins and convert it as an unique js file, or how do you manage when using several of them. It does not look proffesional when listing all of them in the template, it reminds me looking in old website using a bunch of js effects by a bunch of script tags.

I'd really appreciate your help