A slot is a position within a machine on which you insert coins or, in “ticket-in, ticket-out” machines, paper tickets with barcodes. The machine then activates the reels and, if you match symbols, pays out credits according to the paytable. Most slot games have a theme and may include bonus features that align with that theme. You can try out slots in demo mode to see if you like them before playing for real money.

Slot is also a term for a computer expansion card, such as an ISA or PCI (peripheral component interconnect) slot. It may also refer to a space on the motherboard that is reserved for a memory module or other component.

When a slot is filled, it can be used by the software to store data or run a program. It is then possible to access that data or execute the program from a different device without having to connect the computer. This type of slot is often called a “hard disk slot.”

Periodic slots are used to represent data that repeats at a regular time interval, such as a set of evaporation coefficients for a reservoir. The values for each year are based on a combination of variables such as temperature and wind speed, which vary seasonally. If this data were entered into a table slot, the results would need to be repeated for each year, and the time element of the data would be lost. By using a periodic slot, you avoid having to repeat the same data for each year and can instead average the results over each duration.

A periodic slot is identified by a special ornamentation in its header and opens in its own Slot Dialog. When a slot is in periodic mode, it will display a date for the end of the current timestep. This can be changed by clicking on the Date button in the Slot Dialog. Periodic slots also display a special icon on the Slot Viewer to indicate that they are in periodic mode. You can undock a periodic slot from the Slot Viewer by dragging it off to become its own Slot Dialog.

Statistical slots are used to store the results of one or more RiverWare simulations. When a statistical slot is selected, its snapshots are displayed in the slot dialog along with their results. This allows you to quickly compare the result of a simulation with that of a previous run. Typically, these slots are used for comparisons between similar simulations or to determine the relative performance of different algorithms.

Expression slots are a unique type of slot that utilize the RiverWare Policy Language (RPL). In addition to simple expressions, these can contain complex logic and functions that evaluate on a per-slot basis.