If you've been playing MMOs previously, particularly hack-and-slash ones, then you'll be aware that the fastest method to progress is to Path of exile currency take out all monsters in the least timeframe, and the best method to accomplish this is to make use of AoE spells. Actually, the majority of PoE builds focus on dealing AoE damage to clear the map as fast as they can. That's the reason why for many of the endgame builds that aren't designed around that specific technique, a dedicated build for leveling is needed.

Here are some of the most sought-after essential skills that are required to use in Path of Exile leveling builds:

Blade Vortex

Fire Trap

Storm Brand

Static Strike

Armageddon Brand

Cleave

Firestorm

Vortex

Winter Orb

Spark

Purifying Flame

As a side note, There's a constant debate in the PoE community about whether it's more beneficial to have a separate Path of Exile leveling build or to POE buy currency move to the final build as soon as you can.