There is no universally agreed upon answer to how many different "kingdoms" of organisms there are. This is because the classification of life is constantly evolving as new discoveries are made and our understanding of evolutionary relationships deepens.

Historically, the most common classification used five kingdoms:

1. Monera: (prokaryotes, including bacteria and archaea)

2. Protista: (single-celled eukaryotes, like algae and protozoa)

3. Fungi: (molds, yeasts, mushrooms)

4. Plantae: (plants)

5. Animalia: (animals)

However, this classification is outdated and has been largely replaced by a three-domain system proposed by Carl Woese:

1. Bacteria: (prokaryotes)

2. Archaea: (prokaryotes)

3. Eukarya: (all organisms with eukaryotic cells, including protists, fungi, plants, and animals)

Within the Eukarya domain, there are numerous distinct lineages that are sometimes grouped into kingdoms. Some commonly recognized kingdoms within Eukarya include:

* Protista: (a very diverse group of single-celled eukaryotes)

* Fungi: (heterotrophic organisms that absorb nutrients)

* Plantae: (multicellular organisms that produce their own food through photosynthesis)

* Animalia: (multicellular organisms that obtain nutrients by consuming other organisms)

It is important to note that the number and definition of kingdoms can vary depending on the specific classification system being used.

So, the short answer is that there is no definitive answer to how many kingdoms of organisms exist. The classification of life is an ongoing process, and the number and names of kingdoms may change as our understanding of the tree of life evolves.