I don't understand the difference between these terms and google didn't help much. Please answer the question even if you have any slightest idea.
Datum is latin for 'a given', and data is the plural, meaning 'the givens.' If you want to be precise, you should refer to a single observation as a datum and multiple observations as data. Notice that the latter is a plural word: 'The data are [not is] hard to interpret.'
But usage has changed. People, especially in Data Science, usually seem to talk about 'a single data point' and say that 'the data is hard to interpret.' See this discussion for example.
My recommendation: As long as you are talking to Data Scientists and IT guys, ban datum from your vocabulary and use data with the singular. Reconsider once you are a professor in Oxford.
In data science -
Data singular is a single value of any variable. Data plural is all the values of a variable.
A 5, 6, 3, ... B 4, 3, 9, ...
Here Column A and Column B are the variables of data set. 5 is the single value of variable A (data singular) All the values of variable A (data plural)