Mission Statement
Not to be confused by basics. The basics is the basic understanding of the game, inside the game outside of the basics you have things that you need to target while playing. We call these things the "Objectives" these are things you will need to get rid of, in order to win your match.
Turrets

The turrets in this game protect the enemy, and also it protects their base. In order for you to win the game you must destroy the turrets. They also grant gold.
Dragons

There are 4 normal dragons, each game you can get any combinations of what are (from left to right) the Infernal Dragon, The Mountain Dragon, The Ocean Dragon and the Cloud Dragon. They're called the Elemental dragons and each of them give you a different boost.
The Infernal Dragon: Grants you a Damage Boost.
The Mountain Dragon: Grants you a Defense (Armor and Magic Resist) Boost.
The Ocean Dragon: Grants you life regeneration boost.
The Cloud Dragon: Grants you a movement speed boost.
Also after you kill all the dragons, the Elder Dragon spawns, which grants you the ability to instantly kill any of your enemies if they drop under 30% health points.

Rift Herald
Before the Baron spawns, the Rift Herald takes it's place. It's a small objective to secure. But it's really powerful because it does a lot of damage to towers.

Here's a demonstration of it's "Charge" ability, that damages towers:

Baron Nashor

The Baron is another objective on the map, when killed it grants you extra Attack Damage and Ability power. It also powers up your minions:

Inhibitor

When you destroy all the towers, and approach the enemy's base there's an inhibitor. The inhibitor is there to stop Super minions from spawning. When you destroy the enemy's inhibitor, your minions gain the ability to spawn a super minion:

Super minions are much stronger minions that deal more damage, and can tank more hits.
Nexus

The nexus is the end goal of the game. It is guarded by 2 towers. And when you destroy it you win the game.