There are more than 100 different types of arthritis, but here are the seven most common types:

1. Osteoarthritis: This is the most common type of arthritis, which is caused by the "wear and tear" of joints due to aging, joint injuries, or obesity.

2. Rheumatoid arthritis: This is an autoimmune disease where the bodys immune system attacks the lining of the joints, causing inflammation and joint damage.

3. Psoriatic arthritis: This is an autoimmune inflammatory disease that affects people with psoriasis, causing joint pain, stiffness, and swelling.

4. Gout: This is a form of inflammatory arthritis caused by the buildup of uric acid crystals in the joints, leading to severe pain and swelling.

5. Lupus: This is an autoimmune disease that can cause joint pain, stiffness, and swelling, as well as other symptoms such as fatigue, skin rashes, and fever).

6. Ankylosing spondylitis: This is a type of inflammatory arthritis that primarily affects the spine, causing pain and stiffness in the back and neck).

7. Juvenile idiopathic arthritis: This is a type of arthritis that affects children under the age of 16, causing joint pain, stiffness, and swelling).

Its important to note that specific symptoms vary depending on the type of arthritis, but usually include joint pain and stiffness.