Why NASA had to update software for Curiosity rover?

Curiosity Rover

  Have you ever thought of why NASA have to upload software separately to Curiosity Rover?, Why it doesn't have enough memory space?, How can they send these updates to over 160 million miles away?

  Many of us still don't know that, we share you some of its technical specs and why they have to upload a software.  The software for Curiosity Rover had to be updated because Curiosity needed different software to drive around on Mars that it did to land on the planet's surface.

  The computer hardware in the Curiosity Rover is powered by a pair of computers built by BAE systems.  These RAD750 computers use a 10-year-old IBM Power PC microprocessor running at 132 megahertz.  It has just 120 megabytes of random access memory, making it a great computer if you're living in 1995.  But its built to withstand wild temperature swings, radiation and physical shaking.

  The limitation is that the computer on the robot vehicle doesn't have enough memory for both the landing and surface missions.  So NASA had to swap out the software over four days of communication through the void of space.

  It took so long because every interaction takes 14 minutes to send the signal to the rover and 14 minutes to get a response back. I guess you could call that the longest-distance mobile computing that we have seen yet