Jira is a proprietary issue-tracking system. It can be used to track bugs, resolve issues, and manage project functions. There are many tools available on the market, but the best thing about Jira is that it can be easily customized and configured to suit the specific needs of an organisation and there are plenty of ways to add more features.

Out-of-the-box, Jira offers defect/bug tracking functionalities, but it can also be customized to act like a help desk system, a simple test management suite, or a project management system with end-to-end traceability for software development projects.

Jira is mainly accessed using a web browser but it has lot of integrations with other tools and Jira comes with a RESTful API so you can interact with it programmatically.

Jira Core is one of the basic flavors of Jira and targets business teams that need a tool that's flexible, can be customized to their needs, and is easy to use as well.

Jira Core is perfectly suited for teams such as marketing, operations, HR, legal, and finance. It has all of the features of workflows, dashboards, and reports.

The target team for Jira Software—as the name suggests—is a team interested in using a tool that can help them implement Agile methodologies such as Scrum and Kanban.

Jira Software comes with standard features such as creating Agile boards for better transparency. There are features to plan, track, release, and report. It has all of the features of Jira Core so you can be assured that it's powerful enough when it comes to customization.

Apart from business teams and software teams, Jira Service Desk targets support desks or help desks.

In Jira Service Desk, there are the standard features of a service desk tool such as a customer portal to raise tickets and search in the knowledge base for self-serve for customers; for the agents who will be handling the tickets, they have configurable queues. Just like Jira Software, Jira Service Desk also contains all of the features and benefits of Jira Core.

As you must have already guessed, Jira Core is the most basic tool and, based on your requirements and whether you want to develop software using Agile methodologies, the waterfall methodology, or a custom development process, you can use Jira Software. For providing support to your customers and handling tickets in Jira, you can use Jira Service Desk.