making a four port outlet timer

alright i got about half way through that thread and started to get pretty confused it was ver difficult to keep up with when he was having difficulty talking in english.... perhaps I should start by asking a few questions and maybe using someone else code off of another page and modding it to my liking so i can get to learn it more...

firstly.... i didnt ever get to using librarys... from my undestanding you download the library and install it into my uno and it will use it to communicate with the rtc and lcd.. is this true? if so then do i need to tell the rtc to communicate with the lcd as well?

as for the relay shield i believe it is controlled by setting different pins to a high or a low to trigger a relay am i right?