Note that someone not familiar with networking or programming might have said 'Hey, can you check our server?' not realizing that the issue might take much longer than a moment to narrow down and eventually fix.

It is implied that a more thorough examination, lasting for an indeterminate amount of time, is required. Hey, can you check out our server? The web service seems to be down. This is a colloquial slang application of the phrase 'check it' - here the phrase is always used unmodified and is merely used to draw attention to whatever the speaker is referring to. Hey man, check it - I got these new shoes. The statements imply that the 'checking' will take no longer than a moment. This is the normal application of 'check it' and variants of that phrasal structure. I need you to check on Dylan and see if he's feeling well or not. 'Check it out' usually implies that you are going to perform some level of thorough examination. 'Check it out' and 'check it' can have roughly the same meaning, but 'check it' usually implies a quick, routine check, rather than a thorough examination. But I don't understand the meaning of 'check it out'. This is a literal application of the word 'out.' As in, David is holding the box outwards from his body - he is stretching his arms away from his body while holding the box. but if I add 'out' after the word 'held out' (David held out the box) does not make any sense, i.e I can not understand the meaning.

Checkit 3.0