What s MM and what s MC

First and foremost, please excuse my ignorance regarding this question. What does MM and MC stands for? I assume moving mass and moving coil? Feel free to correct me if I am wrong. Secondly, what the difference between MM and MC? I do noticed that some phono stages are only for MM or MC, and others are for both. Thanks in advance for clearing this up.
MM is moving magnet, which has a much higher output than a moving coil in most cases. (There are high output moving coils). If the preamp does not have a MC input, a step up device such as a head amp or transformer is necessary.
There are moving coil (MC) phono cartridges that are high output, and therefore, do not need a MC step-up phono stage preamp, and work fine with a Moving Magnet (MM) only phono setup. Sumiko Blue Light and Blue Light Special are very popular. There are others. Many preamps and separate phono stages can handle both types of phono cartridges. You will need to check the specs.
I guess the rest of your question is: MM & MC are the two major types of phono cartridges. One basically uses some kind of moving (vibrating) electro-magnet to convert the vibration from the record grooves & stylus to an analog electrical signal. The other type uses some type electrical coil to do the same thing. Moving coil tend to be more expensive (can go into the thousands of dollars), and preferred by a lot of audiophiles into only records. There are some very good MM cartridges as well. The Shure V15VxMR is a well regarded MM cartridge for around $250.
Thanks everyone.
Just to clarify a previous response:

Both Moving Magent (MM) and Moving Coil (MC) cartridges rely on the fact that a wire moving in a magnetic field generates an electrical signal.

In a MM cartridge, the coils (one per channel) are fixed. and a permanent magnet attached to the stylus provides the varying magnetic field as it vibrates in response to the record grooves. The MM cartidge benefits include relative ease of manufacture, ruggedness, high output, and user-replacable stylus.

A MC cartidge reverses the mechanical positions of the magenet and the coils. The permanent magnet is fixed, and the coil is attached to the stylus. The coil vibrates in response to the record grooves, thus generating a signal.
This coil has much lower mass than the permanent magnet attached to the stylus of MM cartridge, so the MC cartridge has better transient response than the MM cartridge, and often have a better high end. This comes at a cost - the low mass moving coil contains much less wire than the fixed coils of the MM cartridge, so the MC cartridge has very low output and low impedance, thus requiring a step up transformer and/or special phono preamp.

The MC stylus is not user replaceable. Stylus replacement involves a cartridge rebuild.

There is a third type of magnetic cartridge called a Moving Iron (MI) cartridge. This uses a fixed permanent magnet and fixed coils. A low mass piece of iron (or other magnetic material) sits between the coils and the permanent magnet, and is attached to the stylus. As the stylus vibrates, the attached piece of iron modulates the magnetic field from the permanent magnet. This varying magnetic field generates an electrical signal in the coils.

MI cartridges have all the advanages of the MM cartridge, and have some of the transparency and transient response associated with MC cartridges, since the piece of iron is much lighter than the permanent magnet in the MM design.

The Grado product line consists of MI cartridges
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I need your correct email address, cannot seem to send you and email.
Joe, You have the letter "L" in your address. He does not.