What is the difference between a "cold storage" wallet and a "hot" wallet?
Is it possible to sign a transaction to be sent from cold storage without converting it into a hot wallet?
Cold storages are wallets created offline and maintained offline until you want to make a definitive move with the coins, they are kept safe from hacks or unauthorized access from the Internet since they should never reside on a computer that is or will be connected to the Internet (perfect method for storing coins).
Hot wallets are easily accessible with the Internet like mymonero.com since the seeds are created online you can't ever be 100% sure they can't be compromised.