How do Products, Price Book Entries, and Revenue/Quantity Schedules work together?

Products (Product2 object) are the items or services a company sells. Each product has a product family, product code, and description. A product becomes available for sale by adding a Price Book Entry — the combination of a product and a price book with a specific unit price and currency. Opportunity Products (OpportunityLineItems) link products to opportunities via the selected price book. Revenue Schedules spread an opportunity line item's revenue over multiple periods (e.g., a $120k annual subscription split into 12 monthly $10k increments). Quantity Schedules spread product delivery over time (e.g., 12 monthly shipments of 100 units). Schedules can be established/renewed automatically based on the product's default schedule settings or set manually per line item. Scheduled revenue feeds into forecasting and revenue reports.