What are the types of ovules?

There are two main types of ovules: anatropous and campylotropous. Anatropous ovules are straight and upright, with the micropyle (opening through which the pollen tube enters) at the top. Campylotropous ovules are curved, with the micropyle located near the base of the ovule. Additionally, there are other types of ovules such as orthotropous, hemitropous, and amphitropous, which have variations in their orientation and position of the micropyle.