diff --git a/magick/cache.c b/magick/cache.c
index 178886a..401616c 100644
--- a/magick/cache.c
+++ b/magick/cache.c
@@ -1900,8 +1900,8 @@
% or it may point to the original pixels in memory. Performance is maximized
% if the selected region is part of one row, or one or more full rows, since
% then there is opportunity to access the pixels in-place (without a copy)
-% if the image is in RAM, or in a memory-mapped file. The returned pointer
-% should *never* be deallocated by the user.
+% if the image is in memory, or in a memory-mapped file. The returned pointer
+% must *never* be deallocated by the user.
%
% Pixels accessed via the returned pointer represent a simple array of type
% PixelPacket. If the image type is CMYK or if the storage class is
@@ -3602,12 +3602,12 @@
%
% GetVirtualPixels() returns an immutable pixel region. If the
% region is successfully accessed, a pointer to it is returned, otherwise
-% NULL is returned. The returned pointer may point to a temporary working
+% NULL is returned. The returned pointer may point to a temporary working
% copy of the pixels or it may point to the original pixels in memory.
% Performance is maximized if the selected region is part of one row, or one
% or more full rows, since there is opportunity to access the pixels in-place
-% (without a copy) if the image is in RAM, or in a memory-mapped file. The
-% returned pointer should *never* be deallocated by the user.
+% (without a copy) if the image is in memory, or in a memory-mapped file. The
+% returned pointer must *never* be deallocated by the user.
%
% Pixels accessed via the returned pointer represent a simple array of type
% PixelPacket. If the image type is CMYK or the storage class is PseudoClass,
@@ -4455,8 +4455,8 @@
%
% Performance is maximized if the selected region is part of one row, or
% one or more full rows, since then there is opportunity to access the
-% pixels in-place (without a copy) if the image is in RAM, or in a
-% memory-mapped file. The returned pointer should *never* be deallocated
+% pixels in-place (without a copy) if the image is in memory, or in a
+% memory-mapped file. The returned pointer must *never* be deallocated
% by the user.
%
% Pixels accessed via the returned pointer represent a simple array of type