There are various roles involved while developing any software, in short project development.
There is a series of roles that exist in most software development processes. In some cases, one team member may be filling many roles and some roles may be suppressed for a specific type of project, but all of these roles exist in one form or another in every software development project:
Subject Matter Experts (SME)
The Subject Matter Expert is the person or persons from which requirements are captured. These are the people who know what the software needs to do and how the process works. The SME role is somewhat different from the other roles because it is constantly changing as new clients (internal or external) are brought in to help design a solution. SMEs are rarely from IT -- except when the solution is being designed to support IT. SMEs are most frequently the person who will receive the benefit of the system.
Functional Analysts (FA)
Functional Analysts have the unenviable task of eliciting clear, concise, non-conflicting requirements from the Subject Matter Experts who may or may not understand how technology can be used to transform the business processes in a positive way.
Solutions Architect (SA)
The technical architect is responsible for transforming the requirements created by the Functional Analysts into a set of architecture and design documents that can be used by the rest of the team to actually create the solution. The Solutions Architect is typically responsible for matching technologies to the problem being solved.
Development Lead (DL)
The Development Lead's role is focused on providing more detail to the Solution Architect's architecture. This would include detailed program specifications creation. The Development Lead is also the first line of support for the developers who need help understanding a concept or working through a particularly thorny issue.
The heart and soul of the process, the developer actually writes the code that the Development Leads provided
Quality Assurance (QA)
The Quality Assurance role is an often-thankless position that is designed to find bugs before they find their way to the end customers. Using a variety of techniques ranging from keying in data and playing with the system to formalized, automated testing scripts, the Quality Assurance team is responsible for ensuring the quality of the solution and it's fit to the requirements gathered by the Functional Analyst. Sometimes the QA team is known by their less flattering name of testers.
The Deployment role is the one that packages up all of the compiled code and configuration files and deploys it through the appropriate environments or on the appropriate systems. The Deployment role is focused on getting the solution used. To that end, the role may include automated software installation procedures or may be as simple as copying the files to the appropriate place and running them.
The Training role is responsible for documentation for the system as well as any instructor or computer-based training solutions that are designed to help the users better understand how the system works and what they can do with it.
Project Manager (PM)
The Project Manager is responsible for ensuring consistent reporting, risk mitigation, timeline, and cost control. The project manager role is a problem-solver role. They try to resolve problems while they are small so that they can be handled more quickly and with less cost.
Development Manager (DM)
The Development Manager is responsible for managing multiple priorities of conflicting projects. The Development Manager role is also an escalation for issues from the team, which it is unable to resolve internally. Of course, each organization has its own take on these roles; however, these are the roles you'll see most often in an organization doing development.
Here I have tried to cover all the roles according to my knowledge that are involved project development.