To find out what distribution is best fitting the data.
Use the distribution fitting function Tools=>Distribution fitting. The graph with the highest Correlation coefficient (r²) is the best fitting distribution.
The distribution fitter test for the following distributions:
Normal distribution
Log-normal distribution
Weibull distribution
Exponential distribution
For more information what to do with not normally distributed data see What to do with not normally distributed Data.
Lifetime data is often not normal distributed (wear out). This data is often following the Weibull or Log-normal distribution. For this data use Weibull analysis.
To transform non normal distributed data to a more normal distributed data-set see Box-Cox transformation