Abstract: Human feelings like despair are internal sentiments which might be frequently uncovered by the way the personbehaves. If such feelings can be analyzed and determined from the character's social activities inside the virtual international, it may be very beneficial to recognize these behaviors. To discover depressive moods, detecting words that specific negativity of their social media messages can be step one. depression doesn't just affect the man or woman himself, it can affect his buddies, family, co-workers, and every person around him. in addition, it may have an impact on how he plays at work or his attention level, in short it may negatively affect productivity. To apprehend if an Instagram is a kind system person may want to showcasemelancholy over a period of time, then the gadget might be able to pick out the depressedperson based totally on his postand chats, which incorporates emotional kind key phrases.Keywords: Depression detection, data mining, social media, PDD (Psychological Disorder Detection), OSN (Online SocialNetwork), SNMD (Social Network Mental Disorder) classifier, feature extraction.