Fixed miscellaneous typos, syntactic and grammatical errors.

diff --git a/memory/selector.c b/memory/selector.c
index d5d8df0..06398dc 100644
--- a/memory/selector.c
+++ b/memory/selector.c
@@ -774,7 +774,7 @@
  * Input:   EDI register: size of buffer to allocate
  * Output:  EDI register: pointer to buffer
  *
- * Note: The buffer is preceeded by 8 bytes:
+ * Note: The buffer is preceded by 8 bytes:
  *        ...
  *       edi+0   buffer
  *       edi-4   SEGPTR to buffer