Software Development Life Cycle

SDLC describes phases that provide a model of software cycles and management. Each phase produces what’s needed for the next phase.

The phases of SDLC are:

Requirement gathering and analysis: This phase is about focusing on stake holders and business. You must ask: who is going to use the program? how are they gonna use it? what data should be in the system?
Desing: Based on the requirements from the previous phase, this one consists in defining the software architecture, such as the software and hardware requirements.
Implementation/Coding: This is the most important phase and the longest one.
Testing: In this phase you check if the product was made according to the requirements.
Deployment: The project is delivered to the user. This is a beta testing, the user will evaluate the system and find any errors or bugs. Then the developers will debug the program and finally have the official product.
Maintenance: Taking care of the software.

The models of SDLC are:

Waterfall: This is the traditional model, it consists in finishing one phase to being with the next one..
V-Shaped: Is similar to the waterfull, but focuses more in the testing phase.
Incremental: The cycle is divided in iterations. The software development begins in the first iterarions.
Prototyping: Consists in creating several prototypes of an application.
Spiral: It combines the waterfall and prototyping models.
Extreme programming (Agile): It uses the incremental model, also it is based on the collaboration of cross-functional teams.

I think developing software based on these phases is very important to create good quality projects.

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