A slot is a dynamic placeholder that either waits for content (a passive slot) or calls out for it with a targeter or an Add Items to Slot action. Renderers then use slots to present that content on the page.
In a slot machine, players insert cash or, in “ticket-in, ticket-out” machines, paper tickets with barcodes into a slot on the machine’s face and activate a lever or button to spin the reels. When winning combinations line up on the payline, the player receives credits based on the pay table. Many slot games have a specific theme, with symbols and bonus features aligned with that theme.
The original mechanical slot machine had just one payline that ran horizontally across the top of the machine. As technology improved, manufacturers were able to increase the number of possible paylines by adding additional symbols and shifting existing ones. These changes also allowed the symbols to be weighed differently, increasing the likelihood of a particular symbol appearing on a payline.
In computer science, a slot is an operation issue and data path machinery surrounding a set of execution units (also called functional unit or FU). A slot consists of hardware that implements the basic operating system kernel, such as an interrupt handler, memory management, and virtual I/O. This kernel provides the base functionality of a modern computer. It is sometimes called a microkernel, because it runs directly on the hardware and is insulated from application software.