The Protista encompass the group of organisms that are harder to classify. These (usually) single celled organisms are hard to fit into the typical plant or animal types. As a result, there are three main subkingdoms of the Protista kingdom, protophyta, protozoa, and gymnomycota. The protophyta are more plant like, while the protozoa are more animal like. There is mismatching and crossing over however. For example, the Euglena is in the protozoan subkingdom, but has chloroplasts, which are characteristic of plant cells. Finally, you have the Gymnomycota, the area where they dump the harder to classify of the harder to classify.
Subkingdoms:
-Protozoa
-Protophyta
-Gymnomycota
It should also be noted that the phyla mentioned in the above node are part of the subkingdom Protozoa.