# Autoplan glossary

<table><thead><tr><th width="175">Term</th><th>Definition</th></tr></thead><tbody><tr><td>Master schedule (plan input)</td><td>User input demand for deliverables. Choose the part required, how many are required, and when it is required.</td></tr><tr><td>Material Requirements Planning (MRP I)</td><td>Determines the components required to build an assembly based on supply and demand in the factory. Backwards schedules from the master schedule.</td></tr><tr><td>Material Resource Planning (MRP II)</td><td>Forward schedules dates based on capacity constraints in the factory.</td></tr><tr><td>Order policy</td><td>A way to define how plan items should be grouped or created.</td></tr><tr><td>Period of supply</td><td>A type of order policy that groups plan items by date buckets.</td></tr><tr><td>Plan item</td><td>An output of Autoplan. Plan items can be linked to inventory, runs, or purchases. Or they can be unlinked, meaning that they are a signal to take action.</td></tr><tr><td>Reorder point</td><td>A type of order policy that creates a new plan item purely based on supply levels for a given part.</td></tr><tr><td>Safety stock</td><td>A way to artificially increase demand for a part so that extra parts are kept on hand.</td></tr></tbody></table>