Swear, nothing, not important to remember. Just like those f words you say. Sometimes you can also say, with all due respect, no offense, BUT... (you see, this "but" is what the "hell" is trying to emphasize.) Its official use, you can look it up here: http://dict.youdao.com/search?q=like+hell&ue=utf8&keyfrom=dict.index#q%3Dlike%2Bhell%26ue%3Dutf8%26keyfrom%3Ddict.index [口语]猛烈地 拼命，不顾死活地 过度地；极快地 [俚语]哪有这种事；绝不会

"like hell" = intensifier. = There is no doubt that you do.