What are the differences between cherubim and seraphim? I was reading a post regarding the appearance of angels: What does the Bible say about the appearance of angels?

And I am curious as to the general differences between cherubim and seraphim.
Do they have different appearances, roles, etc? Or are they essentially the same?
Perhaps different sects of faith have differing views.

Do Judaism and/or Christian denominations such as Catholicism note any specific differences between cherubim and seraphim?
Strictly Biblically speaking, the Seraphim are only described once in the Bible:


  In the year that King Uzziah died, I saw the Lord, high and exalted, seated on a throne; and the train of his robe filled the temple. Above him were seraphim, each with six wings: With two wings they covered their faces, with two they covered their feet, and with two they were flying. And they were calling to one another:
  
  
    “Holy, holy, holy is the Lord Almighty;
        the whole earth is full of his glory.”
  
  
  At the sound of their voices the doorposts and thresholds shook and the temple was filled with smoke.
  Isaiah 6:1-4


There really is not much about them. They have six wings and it seems that most of their purpose for existing is to sing praises to God in God's presence. The "doorposts and thresholds shook" at the sound of their voices. These are awesome creatures. No wonder Isaiah was terrified.

Cherubim on the other hand seem to be more simple, having only one set of wings. They are your typical angels and are described in a number of places in the Bible. They appear to look like people with wings. There's a good deal of information on them pretty much everywhere, so I'll neglect to expand on that. It seems their primary purpose for existence is to deliver messages from God to creation, and some suspect from creation to God as well. They also seem to have some multipurpose as soldiers. An example would be the destruction of Sodom and Gomorrah.

Outside of the 66 book Protestant canon there is a lot more information. Tons more. Outside of Christianity there is even more. Much too much for a single answer on this site. FMS's answer hints on some of it.