Digital BW, The Print

A basic PS question:  I am working my way thru Martin Evening's PS book as I try to 
learn more about digital.   I am a little confused by the discussion re Output Levels in 
the Image > Adjustments > Levels section.  Martin always seems to talk in terms of 
half tone printing presses and talks about constraining the output levels (eg 12 to 
243) to suit the press.  What if any alteration to these output levels should I do to 
print on an inkjet printer?   (I predominantly print using my Epson 2100 - both B&W 
and Colour but would also like to deliver content to larger format Epson printers or 
even a Lightjet printer at a lab.)

Thanks in advance

Steve