Yo people how are you doing. I figured i best make a list of all enchantments and there effects.

For sword:
Bane Of Arthropods : Does more damage to spiders
Looting : Gives you more loot
Sharpness : More chance of crits
Fire Aspect : Sets enemy on fire on hit
Knock back : Knocks enemy back more
Smite : No idea

For shovel
Efficiency : Makes it faster digging
Unbreaking : More durability
Fortune : Drops extra blocks

For axe
Efficiency : Makes it faster digging
Unbreaking : More durability
Fortune : Drops extra blocks

For Pickaxe
Efficiency : Makes it faster digging
Unbreaking : More durability
Fortune : Drops extra blocks

For helmet
Protection : Gives you protection. Lol (Take less damage)
Respiration : No idea, maybe give you healing?
Aqua Affinity : Gives you more breath
Blast Protection : Makes you take less damage from explosions
Projectile Protection : Makes you take less damage from arrows and eggs. Lol

For chestplate
Blast Protection : Makes you take less damage from explosions
Projectile Protection : Makes you take less damage from arrows and eggs. Lol
Protection : Gives you protection. Lol (Take less damage)

For legs
Blast Protection : Makes you take less damage from explosions
Protection : Gives you protection. Lol (Take less damage)
Projectile Protection : Makes you take less damage from arrows and eggs. Lol
Fire Protection : Makes you take less damage from fire

For boots
Feather falling : Take less falling damage
Blast Protection : Makes you take less damage from explosions
Projectile Protection : Makes you take less damage from arrows and eggs. Lol
Fire Protection : Makes you take less damage from fire

And that is all i could find. Comment if you find any others. If you are wondering how i got to know these i used a program called NBTEdit, it lets you edit all sort of values including levels.