Depending on a situation, you will have to deal with different types of press releases. Just as life does not stay in the same genre all the time, your press releases will have to correspond to the situation.
The good news is – the basic requirements stay the same for all types of press releases. They will have to:

1. Inform about an event.
2. Explain why the event takes place and what will happen.
3. Give information on when and where everything takes place.

Now add to these requirements particular features, and you will get one of several types of press releases.

1. Regular press releases. This is a document that media and organizations get in the most cases. It informs on a particular event, like a contest, planned press conference, etc.
2. Event press releases. It has much in common with a regular press release, but has to be more detailed. As a sender, you have to explain your addressees what is going to happen, where and, most important, why. Usually, additional information contains a list of guests (if it is a specialized press conference), experts taking part in it, events that are planned, and questions to be discussed.
3. Start-on releases. This one is a condensed form of an event press release. If you want to make fuss around a certain opening, send it to media that might be interested in taking part.
4. Product press releases will contain specialized information on a new product that a company offers.
5. Expert press releases. These contain more general information or such press releases have commercial targets masked under unbiased statistical information, data from third parties, etc.