Software Development Life Cycle

SDLC is a process followed for a software project, within a software organization. It consists of a detailed plan describing how to develop, maintain, replace and alter or enhance specific software. The life cycle defines a methodology for improving the quality of software and the overall development process..
It is also called as Software development process.  
The software development life cycle (SDLC) is a framework defining tasks performed at each step in the software development process.

1. Requirements gathering :
Gather as much information as possible about the details & specifications of the desired software from the client. This is nothing but the Requirements gathering stage.
Business analyst will gather all the information from the customer and prepare Business Requirement 
Specification (BRS) or User Requirement Specification (URS) documents. Senior business analyst will prepare System Requirement Specification (SRS) documents.

2. Analysis :
The features and the function that need to be put in the project are determined / analyzed.

3.Design :
This is done by the chief architect HLD and LLD are prepared.
HLD  - Defines the overall hierarchy of the function i.e. system architecture and design .
LLD   - Defines the internal logic of the project . i.e. actual software components are implemented.

4.Development :
Based on design document small module are summed together and developed.

5. Testing :
Testing phase is done by testing engineer. Different types of testing are performed.

6. Implementation & Maintenance :
Engineer with the coordination of developer will install /implement the developed application .
The testing / maintenance team will suggest to change the software if necessary.