Are you ready to whistle while you work? Let's go over some basics of mining in the world of Minecraft.
There are five types of pickaxes with which you should be familiar: wooden, stone, iron, gold and diamond. As you progress through the different types, each pickaxe can typically mine all of the previous axes' materials along with new varieties.
Starting out, wooden pickaxes can only mine coal, stone, redstone, iron, granite, quartz, and cobblestone. A stone pickaxe can also mine gold and iron. The iron pickaxe adds the ability to mine for diamonds and emeralds. The gold pickaxe is more resilient than iron, but not as resilient as the diamond pickaxe which can mine obsidian.
How do you get these valuable tools? If you're lucky, you may find an iron pickaxe that has spawned inside a chest located in an abandoned mine, a village blacksmith, or a stronghold. You may also be able to trade with blacksmith villagers; they seek emeralds in exchange for enchanted iron and diamond pickaxes. However, most players find themselves having to put themselves to work in order to obtain each kind of pickaxe.
Starting off in survival mode with a starter chest gives you a wooden pickaxe, which can be used to get wood for building a home (although you will likely prefer an ax for that) or to start mining immediately. Try digging down until you hit stone, then mine as much as possible. Next, punch trees for wood. You can then use your crafting table to change the wood into sticks, which will show up in your inventory. Put the sticks and coblstone on the crafting table to create the stone pickaxe. You are now ready to mine for iron in order to can craft your next pickaxe.
To refine any metal ore, you will need a furnace. You may find one in the game (hint: look near blacksmith shops in villages), or you can craft one out of cobblestone. Once you have a furnace at your disposal, refine your iron using coal in the fuel slot and your iron ore in the top. This process will provide you with iron ingots that can be crafted in the same way as the stone pickaxe. Gold ore will need to be refined as well in order to craft it into your gold pickaxe. Continue the progress until you are ready to mine for diamond and craft the final pickaxe, though not being a metal ore it does not need refining prior to crafting.
Be aware that mobs love caves, so you've best brought swords, armor, and food in case you need to make a stand!