They give clients "permission" to access servers. If a client accesses a server and there's no CAL for that client, you're in violation of your licensing agreement. They're kept on paper basically.

As of August 1, Microsoft will raise the prices of a number of its User client-access licenses (CALs) by 13 percent. The affected CALs are for on-premises, not cloud, products. The prices of Device ...

As Microsoft phases out older Exchange Server versions, IT leaders are facing new decisions about how to stay compliant and cost-efficient. Understanding the current licensing landscape for Windows ...

Microsoft has increased the prices of its on-premises server products and Client Access License (CAL) Suites by up to 20%. Organizations will have to decide whether to stay or go to Cloud products.

Remote Desktop Protocol (RDP) basically helps us to connect two systems at a distant location. We’ve already seen how to enable, disable the Remote Desktop connection using the RDP protocol. However, ...

Unless you're running a large company that wants to install, host and maintain Microsoft Exchange Server on its own equipment, you generally don't need to purchase an Exchange Server license.