I want to use VIM help to search for some command abbreviations such as what does the token g and d mean in the following Ex-command::/<table>/,/<\/table>/g/^$/dThis is an excerpt from this website. The above command without g does not work and I do not know why it is mandatory. I am not familiar with how to use help for abbreviations such as these and for particular modes such as insert mode. 
Vim searching help for command abbreviations
help system;abbreviations