On-Premise - This type of intranet is hosted entirely on-site of a business organisation. Their servers are managed, updated and backed-up by a dedicated IT team. However, due to their complexity, it’s mainly just large enterprises that have the capability to dedicate enough resources to on-premise intranet maintenance.
Cloud-based - Most modern intranets are cloud-based, meaning it’s instantly made, maintained and available online. This negates any need to build and maintain any on-premise infrastructure.