nn[1]=Round[RandomReal[NormalDistribution[0,12],100]];
nn[2]=Round[RandomReal[NormalDistribution[23,1],100]];
nn[3]=Round[RandomReal[NormalDistribution[-5,1],100]];

pocetnost[1]=BinCounts[nn[1],{Min[nn[1]],Max[nn[1]]+1}]
pocetnost[2]=BinCounts[nn[2],{Min[nn[2]],Max[nn[2]]+1}]
pocetnost[3]=BinCounts[nn[3],{Min[nn[3]],Max[nn[3]]+1}]

tp[1]=Tally[Sort[nn[1]]];
tp[2]=Tally[Sort[nn[2]]];
tp[3]=Tally[Sort[nn[3]]];

hodnoty[1]=tp[1][[All,1]];
hodnoty[2]=tp[2][[All,1]];
hodnoty[3]=tp[3][[All,1]];

pocetnost[1]=tp[1][[All,2]];
pocetnost[2]=tp[2][[All,2]];
pocetnost[3]=tp[3][[All,2]];

<<"BarCharts`"

<<"Histograms`"

BarChart[pocetnost[1],BarLabels->hodnoty[1]]
BarChart[pocetnost[2],BarLabels->hodnoty[2]]
BarChart[pocetnost[3],BarLabels->hodnoty[3]]

BoxWhiskerPlot[nn[1],BoxOutliers->All,BoxOrientation->Horizontal,BoxOutlierMarkers->{●}]
BoxWhiskerPlot[nn[2],BoxOutliers->All,BoxOrientation->Horizontal,BoxOutlierMarkers->{●}]
BoxWhiskerPlot[nn[3],BoxOutliers->All,BoxOrientation->Horizontal,BoxOutlierMarkers->{●}]