Amphibians are plants and animals that live on both land and water. They are a unique group of organisms that have adapted to live in both terrestrial and aquatic environments. Amphibians include frogs, toads, salamanders, and newts.

Characteristics of Amphibians:
- Amphibians have a dual life cycle, starting as aquatic larvae and then transforming into terrestrial adults.
- They have moist, permeable skin that allows for gas exchange, enabling them to breathe through their skin.
- They have a three-chambered heart, which is less efficient than the four-chambered heart of mammals and birds.
- Most amphibians lay eggs in water, where the larvae hatch and live until they undergo metamorphosis into adults.

Adaptations for Living on Land and Water:
- Amphibians have lungs for breathing air when they are on land.
- They have webbed feet or sticky pads to help them move efficiently in water and on land.
- Their skin is thin and moist, which helps them absorb oxygen from the air and water.
- They have a streamlined body shape to aid in swimming.

Examples of Amphibians:
- Frogs and toads are examples of amphibians that spend most of their adult lives on land but return to water to breed and lay eggs.
- Salamanders and newts are examples of amphibians that spend a significant portion of their lives in water, with some species remaining permanently aquatic.

Conclusion:
Amphibians are plants and animals that have adapted to live in both terrestrial and aquatic environments. They have specific adaptations that allow them to thrive in both habitats. Understanding the characteristics and adaptations of amphibians helps us appreciate the diversity of life on Earth and how organisms have evolved to survive in different environments.

The Animals which live both on land and water are called Amphibians. e.g. Frog.