Samsung Galaxy S2 ClockworkMod Recovery Mode is the advanced version of the Samsung Galaxy S II Recovery Mode that comes along in stock firmware. Besides features like apply update from SD card, wipe data / factory reset and wipe cache partition, ClockworkMod Recovery Mode has addition features like install zip from sdcard, backup and restore, mounts and storage, advanced and power off.

I have been using Android HTC HD2 for quite some time. However, native Android phone like Samsung Galaxy S II does not have ClockworkMod Recovery Mode like Android HTC HD2. Samsung Galaxy S2 does have recovery mode but with less features compare to ClockworkMod Recovery Mode. Samsung Galaxy S2 has Android system recovery <3e> which can apply update from SD card, wipe data / factory reset and wipe cache partition only.