diff --git a/shell.asm b/shell.asm
index 36ed9ad..ebcf736 100644
--- a/shell.asm
+++ b/shell.asm
@@ -15,6 +15,9 @@ struc window
 	.size:
 endstruc
 
+WINDOW_ID_ICON equ 0
+WINDOW_ID_FILE_WINDOW equ 1
+
 WINDOW_MOVE equ 1
 WINDOW_RESIZE equ 2
 
@@ -58,23 +61,22 @@ initialize:
 	mov ax, cs
 	add ax, 0x000
 	xchg [es:GLOBAL_WINDOW_CHAIN_HEAD], ax
-	mov [windows + 0*window.size + window.next], ax
-	mov word [windows + 0*window.size + window.width], 5
-	mov word [windows + 0*window.size + window.height], 3
-	mov word [windows + 0*window.size + window.x], 1
-	mov word [windows + 0*window.size + window.y], 1
-	mov word [windows + 0*window.size + window.data], disk_icon
-	mov byte [windows + 0*window.size + window.icon], 1
-	mov byte [windows + 0*window.size + window.mouse_released_inside], 0
+	mov [windows + WINDOW_ID_ICON*window.size + window.next], ax
+	mov word [windows + WINDOW_ID_ICON*window.size + window.width], 5
+	mov word [windows + WINDOW_ID_ICON*window.size + window.height], 3
+	mov word [windows + WINDOW_ID_ICON*window.size + window.x], 1
+	mov word [windows + WINDOW_ID_ICON*window.size + window.y], 1
+	mov word [windows + WINDOW_ID_ICON*window.size + window.data], disk_icon
+	mov byte [windows + WINDOW_ID_ICON*window.size + window.icon], 1
 
 	; Initialize file window but don't show it
-	mov word [windows + 1*window.size + window.width], 40
-	mov word [windows + 1*window.size + window.height], 16
-	mov word [windows + 1*window.size + window.x], 10
-	mov word [windows + 1*window.size + window.y], 4
-	mov word [windows + 1*window.size + window.data], file_window
-	mov byte [windows + 1*window.size + window.icon], 0
-	mov byte [windows + 1*window.size + window.mouse_released_inside], 0
+	mov word [windows + WINDOW_ID_FILE_WINDOW*window.size + window.width], 40
+	mov word [windows + WINDOW_ID_FILE_WINDOW*window.size + window.height], 16
+	mov word [windows + WINDOW_ID_FILE_WINDOW*window.size + window.x], 10
+	mov word [windows + WINDOW_ID_FILE_WINDOW*window.size + window.y], 4
+	mov word [windows + WINDOW_ID_FILE_WINDOW*window.size + window.data], file_window
+	mov byte [windows + WINDOW_ID_FILE_WINDOW*window.size + window.icon], 0
+	mov byte [windows + WINDOW_ID_FILE_WINDOW*window.size + window.mouse_released_inside], 0
 
 	call request_redraw
 
@@ -141,7 +143,7 @@ paint:
 	mov bx, [si + window.next]
 	call forward_event
 
-	cmp si, windows + 1*window.size
+	cmp si, windows + WINDOW_ID_FILE_WINDOW*window.size
 	jne .not_file_window
 	.file_window:
 		; See if the dirents have changed since we rendered the
@@ -514,10 +516,10 @@ show_file_window:
 	mov ax, cs
 	add ax, 0x001
 	xchg [es:GLOBAL_WINDOW_CHAIN_HEAD], ax
-	mov [windows + 1*window.size + window.next], ax
+	mov si, windows + WINDOW_ID_FILE_WINDOW*window.size
+	mov [si + window.next], ax
 
 	; Populate file window contents
-	mov si, windows + 1*window.size
 	call render_file_window
 
 	pop ax