What is Hardcore programming? What is the definition?

what is pure definition, ‘hardcore programming’  ?

@ashok The most common definition of the word 'hardcore' is being diehard, staunch, dedicated or committed. So by that definition, hardcore programming means being up an 'expert in programming'. You could say that hardcore programming means any of the following -

• Being proficient in multiple application development languages
• Expert level security skills
• Always up to date on the latest technology about programming.

Does that answer your question?

Diehard programming or diehard programmer is a general term used to describe someone who enjoys programming and keeps improving his/her skills-set by learning new programming languages and associated tools. 

There's no 'definition' of diehard programming. What was the background for this question, anyway?