A
somatic cell that divides
mitotically goes through two main phases: the
mitotic phase and
interphase. The mitotic phase is short and consists of
mitosis, the division of the
nucleus (which itself consists of some 4-5 phases depending on your sources), and
cytokinesis, the division of the
cytoplasm.
The interphase is much longer, often accounting for about 90% of the cycle. During this phase, the cell grows and copies its chromosomes in preparation for cell division. Interphase consists of three subphases: G1 phase, S phase, and G2 phase. G1 and G2 stand for "first gap" and "second gap" respectively, and S stands for "synthesis". Proteins and cytoplasmic organelles are produced during all three subphases, and the chromosomes are also replicated during S.
After G2 the cell undergoes mitosis (M), after which the daughter cells may repeat the cycle.