What is the difference between a normal laptop and a laptop second gen?

i am looking to buy this laptop http://configure.us.dell.com/dellstore/config.aspxoc=anav15rtest&m_2=I32310M&m_3=3GB2D13&m_6=UMADL6N&m_8=500GB54&m_11=W71HP6E&m_16=8XDVDRW&c=us&l=en&s=dhs&cs=19&model_id=inspiron-15r-n5110 and i dont know what a 2nd gen mean