Application lifecycle management (ALM) is the supervision of a software application from its initial planning through retirement. It also refers to how changes to an application are documented and tracked.
ALM is a very broad term that reflects a change in attitude towards software development that is also expressed in the term DevOp. DevOp is the blending of tasks performed by a company's application development and systems operations teams. In the past, a development team might work independently using a waterfall development model and hand off the completed software application to an operations team for deployment and maintenance. Today, it is more likely that developers will use an agile model and remain involved with the application after deployment, working with business owners and operations to make incremental changes as needed.
There are many ALM tools available for tracking application changes. These range from dedicated ALM products that monitor an application from inception to completion, automatically sorting files into logical buckets as changes are noted, to simple wikis that require team members to record changes manually.