<<"BarCharts`";<<"Histograms`";<<"PieCharts`"

data=Table[RandomReal[],{i,1,10000}];

Histogram[data]

Mean[data]
StandardDeviation[data]

data2=Table[((RandomReal[]+RandomReal[])/(2.`)),{i,1,500000}];

Histogram[data2]

Mean[data2]
StandardDeviation[data2]

data3=Table[(((∑_(i=1)^5)RandomReal[])/(5.`)),{i,1,500000}];

Histogram[data3]

data4=Table[(((∑_(i=1)^50)RandomReal[])/(50.`)),{i,1,500000}];

Histogram[data4]

Mean[data4]

StandardDeviation[data4]