diff --git a/hpvm/docs/hpvm-specification.md b/hpvm/docs/hpvm-specification.md
index 9a776af7df129a072ab4179e7dead15679496db0..640618207bcc6847ff4302899eda8b20abf90d88 100644
--- a/hpvm/docs/hpvm-specification.md
+++ b/hpvm/docs/hpvm-specification.md
@@ -39,9 +39,9 @@ In an HPVM program, the host code is responsible for setting up, initiating the
 - **Initialization and Cleanup**:
 All HPVM operations must be enclosed by the HPVM initialization and cleanup. These operations perform initialization and cleanup of runtime constructs that provide the runtime support for HPVM.
 - **Track Memory**:
-Memory objects that are passed to dataflow graphs need to be managed by the HPVM runtime. The HPVM runtime includes a memory tracker for recording the location, or tracking, of HPVM-managed memory objects. Track memory starts tracking specified memory object.
+Memory objects that are passed to dataflow graphs need to be managed by the HPVM runtime. Our memory model assumes two separate address spaces for host and device memory. The HPVM runtime includes a memory tracker for tracking the location of HPVM-managed memory objects between these address spaces. Track memory inserts the specified memory object in the memory tracker and starts tracking it.
 - **Untrack Memory**:
-Stop tracking specified memory object.
+Stop tracking specified memory object and remove it from memory tracker.
 - **Request Memory**:
 If the specified memory object is not present in host memory, copy it to host memory.
 - **Launch**: