updates

windows/security/operating-system-security/data-protection/bitlocker/index.md

@@ -24,6 +24,17 @@ On devices that don't have a TPM, BitLocker can still be used to encrypt the ope
 
 In addition to the TPM, BitLocker has the option to lock the normal startup process until the user supplies a personal identification number (PIN) or inserts a removable device (such as a USB drive) that contains a *startup key*. These security measures provide multifactor authentication and assurance that the device can't start or resume from hibernation until the correct PIN or startup key is presented.
 
+:::row:::
+  :::column span="2":::
+    *BitLocker preboot screen with PIN*
+    :::image type="content" source="images/preboot-pin.png" alt-text="Screenshot of the BitLocker preboot screen prompting to enter a PIN." lightbox="images/preboot-pin.png" border="false":::
+  :::column-end:::
+  :::column span="2":::
+    *BitLocker preboot screen with startup key*
+    :::image type="content" source="images/preboot-startup-key.png" alt-text="Screenshot of the BitLocker preboot screen prompting to enter a PIN." lightbox="images/preboot-startup-key.png" border="false":::
+  :::column-end:::
+:::row-end:::
+
 ## System requirements
 
 BitLocker has the following requirements: