Promoters are the investors in the company. They are the owners of the company and have the right in profits of company. Promoters hold the shares of a company. Anyone can be a promoter of the company, its not necessary that a promoter is a directors.
Directors are managers of company who manages the day to day operations of the company. It is not necessary that the directors are the promoters of the company.
But the basic conditions are there should be 2 promoter and directors in any Private Limited Company. For example in ABC Private Limited