What do the Green and Blue lines indicate on the main graph on the "Yahoo Finance Premium" site?

I've just now started investing in stocks. I'm a real newbie. I'm trying to track my stocks using "Yahoo Finance Premium". I got the "Premium" free for 14 days. I have no clue what it's telling me. For instance:

What do the Green and Blue lines indicate on the graph showing my portfolio indicate?

What on the Yahoo Finance site should I be watching for?

I did put in my portfolio of stocks. They seem to be doing alright except for Google. I've invested about  $2000 in 7 stocks and two cryptos. I intend to invest more once I get the hang of things.

By the way, I used Robinhood. I now know this wasn't the best choice and am considering switching. But I understand it'll take a week to get all my money out of it. And if I do, I'll lose $20 because of the Google stock.
What do you think?

2017-04-11T00:37:33.809Z