Broadly, political parties can be classified based on the kind of programme or platform that they endorse and which they try to enact once they've gained power.
Left or leftists is a party that desires and backs anything that is considered a progress. They want to change major aspects of life. In general (but not always) the left parties were secular, republican (as opposed to monarchy), socialistic, promoting ecology, women's suffrage etc.
Right party is usually conservative, that desires status quo and accepting progress, but wanting it to go its own way. In general these parties are religious, monarchistic (as opposed to republic), nationalistic etc.
The hawks is a party or group of people that promotes declaring or joining a war. They are opposition of doves who do anything to keep peace.
Patronage parties exist to dispense offices and other privileges to the party's supporters. These parties are often non-ideological.
Fusion, union, or big-tent parties may be hard to describe with any pat summary. This election's coalition partner may be next election's opponent.
Major political parties in the world endorse broad programmes that contain policy guidance to most major political issues.
By contrast, single issue parties focus on one or few aspects of political life, for example United Kingdom Independence Party was created to perform withdrawal of the united-kingdom from the European Union. Temperance parties have focused on prohibition, green parties focus on the environment, and so forth.
Questions related to history of particular parties in different eras and in different states, countries or territories should be tagged with political-parties. For single issue parties, consider adding a tag that focuses on that issue, like economy, human-rights etc.