Jellyfish are marine animals that belong to the phylum Cnidaria. Here is a description of jellyfish:

- Appearance: Jellyfish have a translucent, gelatinous body with a network of nerve cells, called a "nerve net," that helps them coordinate their movements. They have a bell-shaped or umbrella-shaped body with long, thin tentacles that trail behind them.

- Size: Jellyfish can range in size from just a few millimeters to several meters in diameter.

- Movement: Jellyfish are slow-moving animals that use a form of propulsion called "jet propulsion" to move through the water. They contract and relax their muscles to create a current that helps them swim.

- Feeding: Jellyfish are carnivorous and feed on small fish, plankton, and other small marine animals.

- Habitat: Jellyfish are found in oceans all over the world, from the surface to the deep sea.

- Behavior: Jellyfish are often solitary animals, but some species are known to form large groups or "blooms."

- Reproduction: Jellyfish reproduce by releasing sperm and eggs into the water, which fertilize and develop into larvae that settle on a surface and grow into new jellyfish.

- Stinging cells: Jellyfish have specialized stinging cells called cnidocytes that help them capture prey and defend against predators.

- Bioluminescence: Some jellyfish are bioluminescent, meaning they can produce their own light.

Note: There are many different species of jellyfish, and not all of them have all of these characteristics.

Jellyfish are marine animals that belong to the phylum Cnidaria. Here is a description of jellyfish:

- Appearance: Jellyfish have a translucent, gelatinous body with a network of nerve cells, called a "nerve net," that helps them coordinate their movements. They have a bell-shaped or umbrella-shaped body with long, thin tentacles that trail behind them.

- Size: Jellyfish can range in size from just a few millimeters to several meters in diameter.

- Movement: Jellyfish are slow-moving animals that use a form of propulsion called "jet propulsion" to move through the water. They contract and relax their muscles to create a current that helps them swim.

- Feeding: Jellyfish are carnivorous and feed on small fish, plankton, and other small marine animals.

- Habitat: Jellyfish are found in oceans all over the world, from the surface to the deep sea.

- Behavior: Jellyfish are often solitary animals, but some species are known to form large groups or "blooms."

- Reproduction: Jellyfish reproduce by releasing sperm and eggs into the water, which fertilize and develop into larvae that settle on a surface and grow into new jellyfish.

- Stinging cells: Jellyfish have specialized stinging cells called cnidocytes that help them capture prey and defend against predators.

- Bioluminescence: Some jellyfish are bioluminescent, meaning they can produce their own light.

Note: There are many different species of jellyfish, and not all of them have all of these characteristics.