Topic: BOTW: Please explain what weapon numbers mean

Weapons (also clothes/armor) have all these different numbers.
I'm assuming the numbers on the inventory screen is the attack, or defense in the case of armor.
But select the item and there's 2 more numbers separated by an arrow. Aaaannnd... it makes no sense.
I've googled, searched, and asked other players, nobody knows. So either its so obvious that I'm just retarded, or nobody else knows either.
Help?

The number is the weapons attack or the shields defense.

What you are seeing is a comparison from the item you have currently equipped, to the item you are looking at.

So if you are holding a travelers sword and looking at the claymore:

10 (what you are holding numbers) -> 20 (what you are looking at numbers)

If you equipped the claymore your attack would go from 10 to 20.