Depression, a mental illness that is often characterized by prolonged periods of sadness and melancholy, experts from the field of psychiatry say.
But just because one person is moping around and just generally hating the world around him or her, doesn't mean that it's already depression, but if this kind of behavior, the feeling of emptiness, loss of self-worth and absolutely no hope for happiness just goes on and on, then, yes, that individual is very much, indeed, depressed.
Still, there are various types of depression, from Manic or Bipolar depression - characterized by sudden and extreme changes in one's mood wherein one minute he or she is in an elevated state of euphoria while the next minute (day or week) he or she is feeling to be in a personal hell, Postpartum depression - characterized by a prolonged sadness and a feeling of emptiness by a new mother wherein physical stress during child birth, an uncertain sense of responsibility towards the new born baby can be just some of the possible factors why some new mother go through this, Dysthimia - characterized by a slight similarity with depression, although this time, it's been proven to be a lot less severe, but of course with any case, should be treated immediately, Cyclothemia - characterized by a slight similarity with Manic or Bipolar depression wherein the individual suffering from this mental illness may occasionally suffer from severe changes in one's moods, Seasonal Affective Disorder - characterized by falling in a rut only during specific seasons (i.e. Winter, Spring, Summer or Fall) studies however, prove that more people actually fall in to a rut more during the WInter and Fall seasons and lastly, Mood swings, wherein a person's mood may shift from happy to sad to angry in just a short time.
Clinical depression however, or as some might call as 'major' depression, is actually the medical term for depression. Actually clinical depression is more of a disorder rather than an illness since it basically covers only those who are suffering from symptoms related to depression. Clinical depression is how doctors usually refer to "depression" when giving a diagnose of their patient. It's basically just a medical term.
However, in spite of being an actual disorder, Clinical depression may well be treated. Doctors are actually highly optimistic that their patients who are suffering from Clinical disorder will be well on their way towards good mental health as long as they treated as soon as they have been diagnosed with Clinical depression. Patients who have been seeking for treatments for Clinical depression have proven to be quite successful in their quest, given that 80 percent of actual Clinical depression patients have been treated and has somewhat found relief from their disorder.
For those who may be seeking some answers for their Clinical depression related questions, the depression section of the health center is highly recommended, as well as books on psychiatry and the internet - which can offer a lot of helpful information with regards to Clinical depression although self-medication/treatment is highly disapproved of. Clinical depression may not pose as much as a threat as the other types of depression, but it is best to leave it to the hands of professionals who can safely attend to and cure this disorder.