Cacti are a type of plant that are known for their spines or thorns. These plants are often found in dry, desert-like regions and have adapted to harsh environments with their unique features.

Cacti belong to the family Cactaceae, which is composed of more than 1,500 different species. They come in a variety of shapes and sizes, ranging from small, spherical plants to tall, columnar ones. Some cacti even have branches and can form large, tree-like structures.

One of the most distinctive features of cacti are their spines. These spines are modified leaves and serve as a form of protection against herbivores and other animals that may try to eat the plant. The spines also help to reduce water loss by shading the plant from direct sunlight and creating a layer of still air around the plant.

Cacti are well adapted to survive in arid environments. They have a shallow root system that allows them to quickly absorb water when it does rain. Cacti also have a thick, fleshy stem that stores water for times when there is no rain. Some cacti can survive for months without water.

In addition to their unique physical features, cacti are also valued for their ornamental beauty. Many species are grown as houseplants or used in landscaping, and some are even used for food and medicine.

Overall, cacti are a fascinating and resilient group of plants that have adapted to thrive in some of the harshest environments on earth. Their spines are just one of the many adaptations that make them truly unique.