intitle
used to search some informasi based on title of a web page
example : you type : intitle:blogspot so the result is a page which used a title blogspot

inurl
used to show the search result which had a keyword that we used to search into the url that we looking for
example : you type : inurl:blogspot so the result that will shown up is a url/webpage which had a blogspot word

site
used to search a keyword that you looking for from just one site and can used to search how many site in a country.
Example : you type : blogspot site:microsoft.com so the result that will shown up is just a thing that connected about blogspot and microsoft.com.