nakute verses naku

[kinoko]

any difference? everyone tells me something different...

[Bueller_007]

any difference? everyone tells me something different...

Generally speaking, if it ends with "く", it's an adverb. If it ends with "くて", it means "and", "but", "and then", "therefore", etc.

Sometimes "く" is the same as "くて". In this case, it is usually followed by a comma. For example:

実験が法則に逆らって行われたことはなく、常に、十分に法則の範囲内で行われた。
(Experiments were never carried out against the rules but were performed always well within them.)

I believe using "く" in this way is literary/formal style.