An active sprint is a sprint which has been started and is now visible in Work mode.
A backlog is a list of the outstanding user stories, bugs and features for a product (Product Backlog) or sprint (Sprint Backlog).
A Burndown Chart shows the actual and estimated amount of work to be done in a sprint. The horizontal x-axis in a Burndown Chart indicates time, and the vertical y-axis indicates cards (issues).
A Control Chart can show the cycle time or lead time for your product, version or sprint. The horizontal x-axis in a Control Chart indicates time, and the vertical y-axis indicates the number of days issues have spent in those statuses.
A Cumulative Flow Diagram (CFD) is an area chart that shows the various statuses of work items for a product, version, or sprint. The horizontal x-axis in a CFD indicates time, and the vertical y-axis indicates cards (issues). Each coloured area of the chart equates to a workflow status (i.e. a column on your board).
Cycle Time is the time taken from when work begins on an issue to when work is completed on that issue.
An epic captures a large body of work. It is essentially a large user story that can be broken down into a number of smaller stories. It may take several sprints to complete an epic.
Your board's filter is a JIRA _issue filter (a _JQL query) that specifies which issues are displayed on your board. To choose which issue filter is associated with your board, see the documentation on Configuring Filters.
A future sprint is a sprint which is being planned in Plan mode but has not yet been started.
A JIRA _issue can be used in different ways depending on how you are using JIRA.
Kanban is a system for visualizing the flow of work and limiting work in progress. Kanban allows a team to reduce waste and focus on delivering customer value.
A Kanban board is a board that was created using either the "Kanban" preset or the "DIY" option (see Creating a Board).
Lead Time is the time taken from when an issue is logged until work is completed on that issue.
A product backlog is a high level list of customer requirements for the project that is owned by the product owner/manager.
A Quick Filter refines the collection of issues displayed on your board. Quick Filters appear immediately below the board name in Work mode and Plan mode. Click a Quick Filter to apply it (click it again to turn it off).
Scrum is an Agile http://agilemanifesto.org/ development methodology where work is completed iteratively over a number of discrete time periods (sprints). For more information, please see this wikipedia reference http://en.wikipedia.org/wiki/Scrum_%28development%29.
A Scrum board is a board that was created using the "Scrum" preset (see Creating a Board).
Scrum of Scrums is a means of scaling Scrum to large, multi-team projects. Scrum of Scrums is the Agile version of what is traditionally known as program management.
A sprint — also known as an iteration — is a short (ideally two to four week) period in which the development team implements and delivers a discrete product increment, e.g. a working milestone version.
A sprint backlog contains the list of tasks that need to be completed to implement the features planned for a particular Sprint. Ideally, each task in a sprint is relatively short and can be picked up by a team member rather than being assigned.
A story or user story is a software system requirement that is expressed in a few short sentences, ideally using non-technical language.
A story point is an estimate of the relative complexity of a story.
A swimlane is a means of categorising issues so that agile teams can see which issues they should work on next.
A task is a unit of work contained within a story.
The velocity of a team is a measure of how much work that the team can handle within a specific time period, i.e. how much of the product backlog can be completed by the team in a sprint. Velocity can be calculated on the basis of story points, business value, hours, issue count, or any numeric field of your choice (see Configuring Estimation and Tracking).
A version is a set of features and fixes released together as a single update to your product.
A wallboard is a type of information radiator that displays vital data about the progress of the development team. Similar to a scoreboard at a sporting event, wallboards are large, highly visible and easily understood by anyone walking by.