Depression is not the same as being sad or upset, which happens to everyone from time to time.  Depression is a common mental health difficulty, and is the second leading cause of disability worldwide.  Depression can cause a range of symptoms and so feels different for each individual.  Commonly, people may feel sad or low, irritable, lose interest in things and feel hopeless.  People often experience changes to sleep and appetite, find it hard to concentrate and lack energy.  Some people may develop thoughts of harming themselves, and in that case should seek urgent help.  Depression is a very treatable condition, and there are a number of effective treatments available.   With the right support, most people make a good recovery .