Slot is a term for an object in a program that is invoked by other components or objects. It can be virtual or physical. If the slot is not called directly, it will report a runtime error.

Slot is part of Web Components technology suite. The slot> HTML element allows for separate DOM trees.

Slot is used to manage air traffic at slot online busy airports. In the 1980s, slot machine manufacturers began to incorporate electronics into their machines. These electronic components have allowed for the development of advanced bonus rounds and video graphics.

Slots are also used to receive signals. This allows for a much simpler and more flexible implementation. However, a slot requires overhead for safely iterating over all slots. Emitting a signal connected to a slot is ten times slower than calling a receiver directly.

To use slots for receiving signals, you must define the connection object and marshall the parameters. You can then use QObject::connect() to connect a signal to a slot.

When emitting signals to a slot, the overhead only applies to system calls in slots. This means that only a very small percentage of function call costs will be incurred.

When the sender or context of a lambda is destroyed, it will be disconnected. To prevent infinite looping, setValue() is used to specify the value.

For slot receivers, the receiver may be mixed between both sides of the field. Slots can also be used to receive a signal from a private slot.