There are a whole range of microphones for different applications. Firstly you can narrow your choice down by what you plan to use your microphone for.
Karaoke Microphones
Designed to be used by anyone, whether it is a little girl singing a love song or a macho man belting out heavy metal, the microphone has to be versatile to accommodate all types. Karaoke microphones are generally wireless and some of the more complex ones have thousands of songs built in as well as recording capabilities.
Live Music Microphones
Life on the road can be a bit rough, so you need a microphone that can withstand the knocks of being packed up and unpacked every night. Dynamic microphones are the best, there are loads to choose from, they’re easy to replace, not too expensive and fairly versatile.
Camcorder Microphones
If you want to enhance the audio quality of a video recording then a camcorder microphone is just the job. They are usually stereo microphones that fit to the body of the camcorder. However, if you are recording something like a live show, a stand alone microphone might be preferable to get the best quality recording.
Internet Call Microphones
If you want to use Skype or G-Talk you will need a Microphone attached to your PC. You may also need speakers but at a fraction of the cost you can buy headsets with both! These are very easy to use and leave you hands free so that you can continue to type as well.
Voice Recording Microphones
Some microphones sound better with a female voice than male and vice versa. A good producer should be able to advise you of the right one for you. Usually the best microphones for the studio are condensers. Ribbons are also very good but more expensive.
Studio Microphones
A good studio should have the right Microphone for the job. They would probably have condensers, dynamics and maybe a ribbon. Because you are using the microphones in a controlled environment it should be possible to get the best one for the job that suits the recording.
Drum Microphones
Usually strong dynamic microphones, there are some drum kits that include dedicated microphones for the kick, snare, toms, and maybe hat and overs.
Podcasting
If you want a bit better quality than your standard PC microphone then desktop computer microphones with a cardioid polar pattern works really well and are quite affordable. In general any dynamic microphone would do the job.