Investigation of any process in biology and actually in every field need to examine component of that things , should refer to its basis and sources. this is the main idea for investigation of every thing in the world .Without any waiver ,Most important ,smallest and major living unit that made human able to being alive and continue to livingnamely called “cell” . This efficient, effective, specializeda andmain part of building of all organs in the body. This is very row thinking if thought the division of cells is just for surviving also for being alive and continue to live another situations plays a big role as well, some definition like stability , breathing ,excreting and others.so need to divide and reproduce. In better concept cells are dividing for two reasons, firstly, make themselves widespread = growth, secondly when damaged because of chemical or physical effects or aged because of passing time . each kind of division(mitosis or mitosis) consists of several successive stages, in which the order and occurrence is important. Biologists refer to these steps and the process of producing a new cell with the word “cell cycle”The cell cycle is a regular process with regular events that allows the cell to produce a new cell or a daughter cell, which is why sometimes used the term “cell division” instead of the word “cell cycle.”What is the role of cell cycle in life? an important role in the duration of the generation of any living creature which are assumed as uekaryote . Production of a daughter cell is possible only by the mother cell, not another source. Because of this, the production of synthetic cells in a laboratory is usually difficult and to some extent impossible.If looked closely at the cell cycle, will see two main subsets: the long section or the interphase, and the short section or mitosis , each of which consists of several sub-sets, which will be described in detail.Most of the cell’s life spands over long periods or “interphases”.The cell, before division, simulates all its genetic data and organs so that after division,Inorder to each of the created cell being able to survive and continue to living . All these preparations are in Interphase .Interphase have three sub-phases called G1, S, G2 . ” G ” is abbreviations of “growth” tearm means widening . “S ” is abbreviations for “synthesis”, which means copying the genetic material.