What is the meaning of Cracking?

The thermal decomposition of a substance, especially that of crude petroleum in order to produce petrol / gasoline.

The formation of cracks on a surface.

The production of a crack sound.

That cracks; that produces a sharp sound as of something splitting or breaking.

Great.

Enjoyable.

Very, usually associated with praise.

present participle and gerund of crack

Source: wiktionary.org