According to the PMBOK, a Project Life Cycle has five phases which are as follows:

Initiating : The Initiating phase involves identifying what is needed to start the project successfully. In this phase, you need to develop a business case, a feasibility study, identify the team members, and setup the project.

Planning : During this phase, you need to develop a schedule, plan the resources, develop a budget, and acceptance criteria. During the planning phase, you must define the actions required to achieve the objectives for which the project was assigned.

Executing : During this phase, is when all the actions that were defined in the planning phase take form.

Monitoring and Controlling : During this phase, you must keep track of the deliverables for the project. As a team, you must determine what metrics must be in place to keep track of the project deliverables to make sure the project is complete on time and under budget.

Closing : During this phase, you must ensure that the objectives have been met. This is done by making sure that everything within the Acceptance Criteria set at the beginning is met. Keep in mind that the customer must sign off on the project for the project to be considered successful.