System Development Life Cycle: Basics to Know

Being firstly introduced in the 1960s, the system development life cycle (SDLC) takes its origin literally with the development of the first software systems. So far, the SDLC has gradually transformed into a complex model of the software development process, that can be clearly seen and used within a specific software development model.

Stages of System Development Life Cycle Coding

In this article, Intellectsoft’s best experts have covered the basic information you should know about the system development life cycle: its core meaning and phases, major software engineering methodologies, and the most valuable benefits it can provide for project development.

As a part of our discussion, you’ll uncover the specific characteristics of each of the 7 SDLC phases and why each of these is required to implement either a new or modified software system.

Let’s get this started!

What is the System Development Life Cycle (SDLC)

The system development life cycle (SDLC) is basically a project management model that is used to effectively outline, design, develop, test, and eventually deploy an information system or software product. In other words, it defines the core stages that are important to develop a certain project from the idea or concept to the actual deployment and further maintenance.

SDLC is a general methodology that covers different step-by-step processes needed to create a high-quality software product. The 7 major phases of the system development life cycle include the following and are different from data management life cycle stages which are also crucial:

  • Planning & Feasibility Stage
  • Requirements & Analysis Stage
  • Design & Prototyping Stage
  • Software Development Stage
  • System Testing Stage
  • Implementation Stage
  • Maintenance Stage

Each of these phases requires involving different specialists and a diverse number of skills for successful project completion. That is why, if the budget allows, it’s highly recommended to involve a dedicated team of professional developers that possess enough expertise and knowledge to launch a first-class software product that perfectly corresponds to all your expectations, needs, and goals.

What Are the 7 Phases of SDLC?

Just like we mentioned before, there are 7 separate stages of the system development life cycle process. Now, let’s discuss the core tasks of each stage in detail.

System Development Life Cycle Phases

Stage #1. Planning – What Are the Existing Problems?

Planning is one of the core phases of SDLC, that covers nearly all the upcoming steps the developers should complete for a successful project launch.

This stage helps to set up the problem or define the pain the software can target, define the objectives for the system, and draw the rough plan of how the system will work.

In other words, the planning process helps to come up with the idea of how the specific problem can be solved with a certain software solution. This is critical to help developers better understand the project before they start building software.

Additionally, the planning stage involves analysis of the resources and costs needed to complete the project, as well as estimating the overall price of the software developed.

Finally, the planning process clearly defines the outline of system development, with setting the deadlines and time frames for each of the system development life cycle phases – all these to launch the product by a certain time and present it on the market in time.

Stage #2. Analysis – What Do We Want?

Once the planning is done, it’s time to switch to the research and analysis stage. This step incorporates accumulating more specific data for your new system, including the first system prototype drafts, market research, competition analysis, and more. To successfully complete the analysis and get all the critical information for a certain project, developers can:

  • Generate the system requirements, prioritize them and draw the alternatives
  • Determine the existing prototypes, their pros, and cons
  • Conduct the market research to define the pains and needs of end-consumers
  • Form the concrete system goals and features to target on

Additionally, the analysis stage of SDLC also includes creating the Software Requirement Specification (SRS) document, that defines the software and hardware, functional, and network requirements of the upcoming system development.

As a rule, such a document shapes the strict regulations for the project and sets up the exact software model you want to get in the end result.

Stage #3. Design – How It Should Look Like?

The next stage of a system development project is design and prototyping. Basically, this process is an essential precursor to the core developing stage, which is why it can sometimes be equated with the actual development process.

However, this step of SDLC can significantly eliminate the time needed to develop the software because of outlining of:

  • The system interface
  • Databases
  • Core software features
  • User interface and usability
  • Network and its requirements

As a rule, these features help to finalize the SRS document as well as create the first prototype of the software to get the overall idea of how it should look like.

The design process also includes the first testimonials of the ideas drawn previously, brainstorming some new concepts and solutions that fit better – such an approach can significantly save up the time and costs needed for the software’s actual development. Thus, once the design and prototyping are prepared and the operation plan is ready to go, the creators can finally start programming!

Stages of System Development Life Cycle Team

Stage #4. Development – Let’s Create It

The development stage of SDLC specifically targets the system creation process: the developers write code and build the app according to the finalized requirements and specification documents.

In other words, it includes the front end and back end developing processes. Along with the core functions the software should feature, it includes the UX/UI design of the application – all the basic qualities the product must provide for its end-users.

Developers can utilize the list of different tools and programming environments using C++, PHP, Python, and other languages, that fully comply with the project specifications and requirements

Though this phrase may seem a little bit straightforward, it’s still possible to implement the minor changes and improvements if there are any. However, the efficiency of the finalized version of the system created can be analyzed only in the next stage – the software testing.

Stage #5. Testing – Is It the Exact One We Needed?

Just like for any other system development model, the testing stage is one of the most critical phases of SDLC. After the software is built, it’s even more important to make sure all its features work correctly and coherently, and cannot negatively affect the user experience.

This process involves detecting the possible bugs, defects, and errors, searching for the various vulnerabilities, etc, and can sometimes take up even more time compared to the app-building stage.

In the end, developers usually come up with a testing report that forms up a test case by listing all the issues detected and fixed. Additionally, you can check the testing criteria and ensure the software product meets all the requirements defined by the SRS document.

Stage #6. Integration – How Will We Use It?

Once the product is ready to go, it’s time to integrate it into the specific environment, which usually means its install. At this stage, the software completes the final testing through the training environment, after which it’s ready for the presentation on the market.

Thus, the product becomes available for large audiences!

Stage #7. Maintenance – Let’s Make the Improvements

The last but not least important stage of the SDLC process is the maintenance stage, where the software is already being used by end-users.

Often, during the first couple of months, developers can face the problems that weren’t detected on the testimonials, so they should immediately react to the reported issues and implement the changes needed for the software’s stable and convenient usage. This is particularly important for large systems, which usually are more difficult to test on the debugging stage.

6 Methodologies of System Development Life Cycle

Now that you know what are the basic SDLC phases and why each of them is important, it’s time to dive into the core methodologies of the system development life cycle – the approaches that can help you to deliver a specific software model according to its major characteristics and features.

Overall, there are the 5 most popular SDLC methodologies you can make use of. Let’s discuss the major differences and peculiarities of each:

Waterfall Model

This approach implies a linear type of project phase completion, where each stage has its separate project plan and is strictly related to the previous and next stages of system development.


Waterfall System Development Life Cycle Model

Iterative Model

That incorporates the set of smaller “waterfalls”, where the small portions of changes are carefully analyzed, tested, and delivered through the repeating development cycles. Getting early feedback from the end-user enables the elimination of issues and bugs in the early stages of software creation.

Spiral Model

The spiral model fits best the large projects with similar, more customized products, and enables passing through the main phases again and again, in a so-called “spiral” motion. It enables simultaneous incorporation of the feedback on the first stages of a life cycle, which significantly reduces the time and costs required to implement the changes.


Verification & Validation methodology is super disciplined and requires a rigorous timeline, as the testing phase is incorporated into each stage of the system development, which makes it pretty similar to the waterfall model.

The Big Bang Model

Mostly used for creating and delivering a wide range of ideas, this model perfectly fits the clients that don’t have a clear idea or vision of how their final product should look like.

Thus, the more concrete vision of specific project completion is gained via delivering different system variations that could more accurately define the final output. When it might be too expensive for the delivery of a large project, this SDLC methodology perfectly works for small or experimental projects.

Agile Model

This model is used for the fast and ongoing release cycles and aims at implementing minor but serious changes between releases. This implies more tests and iterations and mostly fits the removing the small issues of the large, more complex projects.

As you can see, different SDLC methodologies are used depending on the specific peculiarities of each project, its requirements, the core vision of the client, and more. Knowing the specific characteristics of each SDLC model can help to pick up the one that fits best to deliver the high-quality, effective product.

Agile System Development Life Cycle Methodology

Benefits of System Development Life Cycle

Having covered the major SDLC methodologies offered by the software development companies, let’s now review whether the system development life cycle is actually worth employing. So, the things you may like about the SDLC models’ implementation are:

  • Defined overview of a system, resources, timeline, and the project goals
  • Setting up a clear guideline for developers
  • Creating a schedule and tracking each stage of the development process and its results
  • Better control over the large and complex projects
  • More detailed software testing
  • The process flexibility
  • Eliminated costs and strict time frames for the product delivery
  • Enhanced teamwork

Possible Drawbacks of SDLC

However, just like any other software development approach, the SDLC models might have drawbacks that can significantly impact the client’s final decision. The probable disadvantages of the software development lifecycle system can be:

  • Increased time and costs for the project development
  • All the details should be specified in advance
  • Low flexibility (especially in the final stages of the project development)
  • The high volume of documentation
  • The attraction of different specialists
  • High involvement of the client
  • Testing might be too complicated for certain teams of developers

Having evaluated all the pros and cons of the system development life cycle, it becomes clear that this approach can surely help you to set up an effective project creating project while keeping always informed about the software creating progress.

Moreover, most of the drawbacks of the SDLC system can also be an advantage for most of the projects that involve detailed planning, more complex development, and strict progress evaluation.

These qualities make the SDLC one of the most beneficial and effective models for the successful launching of a software product.

Stages of System Development Life Cycle


To sum up, the system development life cycle is a complex project management model that encompasses the system creation from its initial idea to its finalized deployment and maintenance.

The SDLC includes 7 different stages: planning, analysis, design, development, testing, implementation, and maintenance – all these are particularly important for delivering a high-quality cost-effective product in the shortest time frames.

Learning the basics of the SDLC performance, its major methodologies, great benefits, and possible drawbacks can help you to set up an ergonomic system development process that will help you to deliver the best outcome.

We, at Intellectsoft, know how essential it is to pick up an effective project management strategy and create innovative software solutions that perfectly fit your business goals and requirements.

Are you looking for the best IT company to develop your software idea?

Contact our team today to uncover how to successfully launch your project with an SDLC approach and benefit from it since day one!

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