diff --git a/xtoskrnl/README.md b/xtoskrnl/README.md
index 189ea95..6ba2a26 100644
--- a/xtoskrnl/README.md
+++ b/xtoskrnl/README.md
@@ -8,6 +8,7 @@ All routines in kernel are prefixed to indicate the kernel subsystem they belong
 This is a list of them:
 
  * Ar - Architecture library
+ * Ex - Kernel Executive
  * Hl - Hardware Abstraction Layer (HAL)
  * Ke - Core kernel library
  * Mm - Memory manager
@@ -20,6 +21,11 @@ the processor, getting the address of a page fault, getting CPUID information, a
 initialization. This module does not contain any manufacturer or board-specific code, only CPU architecture specific
 code.
 
+### EX: Kernel Executive
+The kernel executive supplies heap management, including support for allocating system memory from paged/non-paged
+pools, as well as synchronization primitives like push locks and fast mutexes, interlocked memory access, and worker
+threads.
+
 ### HL: Hardware Abstraction Layer
 Hardware Abstraction Layer (HAL), is a layer between the physical hardware of the computer and the rest of the operating
 system. It was designed to hide differences in hardware and therefore it provides a consistent platform on which