Why are NDS/PSP so popular? (急!!20分)

NDS AND PSP ARE SO POPULAR NOWADAYS ,PEOPLE LOVE TO PLAY THEM BECAUSE OF SEVERAL REASONS.FIRST,AS THE TECHNOLOGY IS IMPROVING SO QUICKLY,BOTH THE NDS AND PSP ARE WITH THE BEAUTIFUL COLOUR MONS NOW,THE COLOURFUL AND ATTRACTIVE PRAPHICS MAKE THEM VERY ATTRACTIVE.SECOND,THERE ARE MANY GAMES CAN GIVE A SENSE OF COMPETITION FOR PEOPLE,FOR EXAMPLE CAR RACING GAMES,BALL GAMES AND FIGHTING GAMES.PEOPLE CAN GET SATISFACTION IF THEY WIN THE GAMES.THIRD,STUDENTS NOWADAYS HAVE TO FACE ALOT OF PRESSURE FROM SCHOOL,IT GIVES STUDENT A CHANCE TO ESCAPE FROM THE PRESSURE OF SCHOOL OR WORK.FORTH,GAMES ARE ALWAYS CHANGING,PEOPLE CAN CHOOSE WHATEVER THEY LIKE TO PLAY.LASTLY,WHEN GAMES START TO BECOME BORING,NEW GAMES COME OUT TO REPLACE THEM,PEOPLE HAVE MANY CHOICES ON CHOOSING THE GAMES,THEY CAN EVEN STORE MORE THAN 100 GAMES IN ONE MEMORY CARD.THIS IS WHY PEOPLE LOVE NDS AND PSP SO MUCH!