What is a party platform? When it is written?

A party platform is a written list of the values and actions supported either by an individual or a political party, which is usually composed in the hopes of generating political party support, such as votes, in regards to controversial and unfavorable topics. They are usually written at crucial times when votes are needed or when issues are highly contentious and divisive, as an initiative for more people to lean towards the ideas written in the party platform.