private key
public key

you'll need Alice's private key to form the signature, and she'll need your public key to verify it
you'll need your own private key to form the signature and she'll need the corresponding public key to verify it
Alice will need your private key to verify the message and you'll need Alice's public key to form the signature
You'll need to talk to Verisign to figure out what the heck you're supposed to do

symmetric keys and hashes
bulk data that we want to encrypt
bulk data that we want to sign
We don't encrypt bulk data directly with public or private keys, because it'd be way too expensive. To encrypt a message, we use a temporary symmetric key to do the bulk encryption, then encrypt THAT key using the target's public key. To sign a message, we hash it first, then encrypt just the hash with the private key to form a signature.

can be sent with a message to prove who the message came from
must be issued by Verisign
helps us associate a name with a public key
Remember that just getting a certificate in a message says nothing about who sent the message. The sender must prove knowledge of the corresponding private key (and prove it's not a replay) before we start to develop trust in the identity of the sender.

you shouldn't tell anyone, or someone will misuse your identity
you should immediately contact the authority who issued your certificate and have them revoke it
you should file a lawsuit against Verisign for disclosing your private key
Verisign doesn't know your private key - that's something you keep to yourself.

requires hardware acceleration because it encrypts payloads using a public key
can only be used with HTTP
normally authenticates the server to the client, as opposed to the other way around as Kerberos does
SSL is a general purpose authentication protocol (although it does require that the underlying network transport be connection oriented, so it runs over TCP, not UDP). It can be used many different application protocols other than HTTP, although HTTP is the most common. SSL does not encrypt payloads using a public key; rather it exchanges a session key and uses that to derive symmetric keys for bulk encryption. Thus connection setup is the only slow part, which can be accelerated in hardware if desired.