It is a web based ticketing system that allows both users and staff to maintain greater control over their tickets and makes communication and resolution of issues a seamless process.
JIRA automatically creates accounts for UMIACS Account holders. 'If you have a UMIACS account, you can log in to JIRA using the UMIACS Single Sign On service. Otherwise, when you email JIRA, a ticket is created, and the email address your mail was sent from is added as a participant to the ticket -- this means that if you create a ticket using a non-UMIACS email address, you'll have to login to JIRA using that email address to see the ticket.
If you have a UMIACS account
Simply login to Jira's Customer Portal  and you will be redirected to the UMIACS Single Single Sign On to login with your UMIACS credentials.
If you do not have a UMIACS account or submitted a ticket with a non-UMIACS address
The first time you use a new address to submit a ticket you will get an automated email containing a link to set a password for the newly-created Jira account. After you have set your full name and password, you can log in with this email address and password at the external user page .