Just imagine you and your family sitting in a line. A tray of food comes and the first member in line eats till he/she is full, then it is passed to next and again he/she eats till stomach is full and so on. In this case, the last member may not receive enough than required. This is the case of series, food is replaced by current and family members by appliances. But in parallel first the current will get divided equally among all the aplliances doesn't matter if it is enough or not.
