Assuming you meet the above mentioned requirements, I'll go ahead and explain uhm.. the game?
Minecraft is a 3D sandbox (sandbox= you can do whatever you like) wich has 2 different gamemodes (actually much more than the 2 standart ones) wich are:
1.
Creative as the name suggests you have all blocks available to "create" anything you like. (ex. Houses, ships, football stadiums ect.)
2.
Survivall its a mode in wich you are called to survive in a randomly generated environment ( find food build a shelter, survive the night when dangerous creatures seek to harm you). In order to survive you have to build a shelter. In order to build a shelter, you have to get blocks. In order to get blocks faster you have to use tools ( axe, shovel, pickaxe..). In order to get those you need materials (wood,stone,iron..).
Consider typing on youtube: How to survive your first night. There are many tutorials on how to play the game.
And when you are exoerienced enough with the game on single player then you'd wanna go online. To join the opticrafts survival server you have to enter its ip wich is: smp.opticraft.net
Before starting, though, Its important that you read the
Information page
[
http://www.opticraft.net/index.php/page,SMPInfo.html ]
Then you'll be able to enjoy the game to its fullest.
I hope this help you
-NoS
