Leak
Leak may refer to any of the following:
1. A term that describes a software issue that causes the computer or hardware device to lose resources that are no longer in use. A leak may be caused when a program does not close properly or by a bug. Commonly, the term leak describes a memory leak, a program that does not release memory resources or retains information no longer being used.
How to tell if your computer has a memory leak
When a leak occurs, you see a drop in your computer's performance or hardware device. For example, with a memory leak, the program may consume the memory until it is exhausted or causes a crash. Microsoft Windows users can identify memory leaks by opening the Windows Task Manager; if a program's "mem usage" never stops increasing, the program is likely exhibiting a memory leak.
How to fix a memory leak
A leak may be temporarily resolved by closing and restarting the program or rebooting the computer or hardware device. To resolve a leak permanently, a patch needs to be installed.
2. With computer security, a data leak or leak is a release of confidential information. For example, Edward Snowden leaked classified information from the NSA (National Security Agency) to mainstream media in 2013.
3. With a computer firewall, a leak is a programs ability to bypass your firewall and leak information to other computer outside your network.
If you're using Microsoft Windows, you can use the LeakTest utility to test if information can be leaked past your firewall.