Internet Explorer 9 (32 Bits) -

: The 32-bit version featured the new "Chakra" JavaScript engine. It utilized a background thread for Just-In-Time (JIT) compilation , allowing users to interact with pages while the browser generated faster code in the background.

: Regular support for most versions of IE9 ended on January 12, 2016 , when Microsoft began requiring users to upgrade to the latest version of IE available for their OS. Internet Explorer 9 (32 bits)

: Interestingly, the 64-bit version of IE9 lacked this JIT compiler, making it up to four times slower than its 32-bit counterpart in JavaScript benchmarks. : The 32-bit version featured the new "Chakra"