What are the different phases of SDLC?

SDLC - stands for Software Development Life Cycle.
It can be divided in to 7 phases they are: 1.Preliminary Investigation (Feasibility Study).
2.Requirement Analysis (Analysis).
3.Design of the System.
4.Software Construction.
5.System Testing.
6.System Implementation.
7.System Maintenance.

It depends on the development process you follow, for example water fall have phases, and others may have iterations and sprints. Most of the answer you received talks about waterfall which is the cause of the most software development failures. 

Phase1 : Requirement gathering and Analysis Phase2 : Design Phase3 : Implementation/Coding Phase4 : Testing Phase5 : Deployment Phase6 : Maintenance

1-Requirement Analysis2-Design3-Implementation4-Testing5-Evolution

M.
Awwad Answer doesn't require any add ;)

Phases in SDLC :

• Requirement Analysis
• Feasibility Study
• Design
• Coding
• Testing
• Installation
• Maintenance

Agree with the experts that the important phases of SDLC are,

1) System study

2) Requirement gathering and analysis

3) design

4) development

5) testing

6) implementation

7) Maintenance

Modern approach:

1. "The Initiating Process Group consists of those processes performed to define a new project or a phase of an existing project by obtaining authorization to start the project or phase." – A Guide to the Project Management Body of Knowledge (PMBOK Guide) Fourth Edition

2."The Planning Process Group consists of those processes required to establish the scope of the project, refine the objectives and define the course of action required to attain the objectives that the project was undertaken to achieve." –PMBOK Guide

3. "The Executing Process Group consists of those processes performed to complete the work defined in the project management plan to satisfy the project specifications." – PMBOK Guide

4. "The Monitoring and Controlling Process Group. Those processes required to track, review and regulate the progress and performance of the project; identify any areas in which changes to the plan are required; and initiate the corresponding changes." – PMBOK Guide

5. "The Closing Process Group consists of those processes performed to finalize all activities across all the Process Groups to formally close the project or phase." – PMBOK Guide

 

Then loopback for any changes starting from2 end4. Then5 if satisfied and requirements were met.

 

resources: https://www.mpiweb.org/Magazine/Archive/US/November2009/TheFivePrinciplesOfProjectManagement