I posted this in the August 1 minor league thread but I feel as thought it might get lost in the shuffle and since so many people were asking about it, or didn't fully understand it I thought I'd make a separate thread so people could easily find it. So, here is my full explanation of what exactly means by 'option years, being optioned, ect.":
Once you are added onto the 40-man roster, you have 3 option years. Say player X was added this past off-season to the 40 man for the first time. This spring training he was sent down, that is one option used. Say he spent the entire year in the minors.
Spring 2011 he was sent down again, that's his second option used. Say he got called up in May, that's fine. Then he was sent back down later in the year, he has only used two option years (2010, 2011)
Then 2012 he was sent down in spring training. That is his third and final option. He can be called up and sent down as many times during any of the three years. Once 2013 comes around, player X CANNOT be sent down without first going through waivers.
So in other words, you have 3 option YEARS. You can be sent down as many times during a season as long as you have an option year left.
Now, there are some exceptions to the rule.
1) A player can gain a 4th option year if he has LESS THAN 5 years of minor league service. (Yonder Alonso falls under this rule. He signed a big league contract in 2008 and was sent down, first option used. Then in 2009 he was sent down, second used. And now this year his third has been used. In 2011 he can be sent down a 4th time because he has less than 5 years of minor league time.)
2) If a player is optioned and recalled less than 20 days after, that option was not used.