Cardioid microphones have a front-focus pattern that primarily captures sound in front of the microphone. It will pick up some sound from the side, but most sounds captured will be in front of the mic.
Omnidirectional microphones capture sound from every direction equally. A podcaster might use this type if they’re expecting to create sound recordings from many different angles. This would typically not be the best choice for podcasters, since it’s likely to pick up a lot of unwanted background noise.
Figure-8 or Bi-directional microphones pick up sounds from two sides. If you’re interested in doing an interview-style podcast you may be interested in this style. Sound will only be captured on the front and the back of the mic, not on the sides.
Shotgun microphones are similar to a cardioid microphone, but the sound pick up is even more directional. This type mic will only pick up sound right in front of it and will block out all other ambient noise.
Switchable/Multi Pattern microphones allow you to switch between directions so you can use your microphone for different situations.
Boom Arm or Stand
Your mic may come with a stand, but if it doesn’t, you’ll want to purchase something to keep it steady. A stand will be less expensive, but a boom arm can come in handy for easily positioning your mic.
Shock Mount
Anything you can use to reduce unwanted noise pollution is worth the extra investment. A shock mount is especially useful for a boom arm, but is also beneficial if you’re using a stand.