By holding left alt if u look in a block for example when u are mining and a dirt block comes infront of you,instead of wasting time and going to inventory to look for a shovel,hold left alt,it will detect where are u looking with ur crossair,then when u are holding left alt it will automatically place a shovel in ur hand from your inventory and break the block.When u release left alt it will transfer back to your pickaxes.In this way we are saving your time

