The number of modules depends on the size and needs of your company. Generally, large organisations will need more modules than smaller ones. The most common modules include Finance, Inventory, Supply chain management and Customer Relationship Management. In addition to the core modules, the Odoo’s app store has over 40,000 paid and free apps available, that can be installed to customise and extend the functionality of your ERP system, making it the worlds biggest enterprise ecosystem in the world.