seL4
= seL4
{c}
A <microkernel> using <security capabilities> to control access to <operating-system kernel> objects, including <IPC endpoints> and <software threads>. An <IPC endpoint> connects cooperating <user-space services>; its <security capabilities> are distinct from the service-defined handle `9` in the <microkernel file-read example>. <Capabilities tutorial by seL4 Project>[Capabilities tutorial, Background: What is a capability?]{ref}