I use a lot of software tools. Most of them tend to give dates and times as absolute - 4 October 2019, 1 November 2019, and so on. Social sharing tool Dlvr.it takes this approach in its feed history:
Conversely, some of the tools give dates and times as relative (as in, relative to the current date and time) - two hours ago, a month ago, and so on. Support software Freshdesk does this in its search results:
Relative timestamps pose a couple of challenges. The first is that it can require a little bit of mental processing to work out when eight months ago actually was; the second is that even if you do that, you are left with a somewhat vague answer. So it was probably February - but towards the start or the end of the month?
The best approach, then, may be to mix both relative and absolute dates and times. Google Ad Manager does this when setting up a campaign: options include 'Immediately' and 'One hour from now'. This requires less mental processing than listing the current date and time, or the date and time one hour from now.
Facebook also switches from relative to absolute in its news feed. Very recent items will be given a relative time - '2 hrs', '4 hrs' and so on, up to 'yesterday'; Facebook then switches to absolute time.
Perhaps, then, it's best to use relative timestamps for anything happening yesterday, today, or tomorrow; and absolutes for anything outside that narrow, easily understandable window.
Facebook and Dlvr.it do something else interesting. Hover over an absolute timestamp in Dlvr.it, and it will show the relative; hover over a relative timestamp in Facebook, and it will show the absolute:
That's actually pretty useful. 'Ah, so it was 22 hours ago - what time was that then? Oh, 9:21 - got it.'