Jira comes with a number of built-in fields. You have already seen a few of them in the previous chapters. Fields such as summary, priority, and assignee are all built-in. They make up the backbone of an issue, and you cannot remove them from the system. For this reason, they are referred to as system fields.
The following table lists the most important system fields in Jira:
| System field | Description |
| Assignee | This specifies the user who is currently assigned to work on the issue. |
| Summary | This specifies a one-line summary of the issue. |
| Description | This provides a detailed description of the issue. |
| Reporter | This specifies the user who has reported this issue (the majority of the time, it is also the person who has created the issue, but not always). |
| Component/s | This specifies the project components the issue belongs to. |
| Effects Version/s | This specifies the versions the issue effects are found in. |
| Fix Version/s | This specifies the versions the issue will be fixed in. |
| Due Date | This specifies the date this issue is due. |
| Issue Type | This specifies the type of issue (for example, Bug and New Feature). |
| Priority | This specifies how important the issue is compared to other issues. |
| Resolution | This specifies the current resolution value of the issue (for example, Unresolved or Fixed). |
| Time Tracking | This lets users estimate how long the issue will take to be complete. |