Would like to understand some excel vba code

Option Explicit

Sub CompareInterpolation()
    Dim wsOriginal As Worksheet, wsInterpol As Worksheet    'Worksheets
    Dim rwOriginal As Long, rwOriginalMax As Long           'variables to hold numbers
    Dim rwInterpol As Long, rwInterpolMax As Long           'variables to hold numbers
    Dim arOriginal() As Variant, arInterpolData() As Variant, arInterpolResult() As Variant     'array variables that can hold any type of data
    Const Limit As Single = 0.02
    'setting each of the worksheet variables to a specific worksheet in the active workbook
    Set wsOriginal = Worksheets("Original Data")
    Set wsInterpol = Worksheets("Intepolation")     'This worksheet name might be misspelled
    'These are taking a count of how many rows are contained in the sheet that are bounded by any combination of blank rows or columns
    'A better way would be to use wsOriginal.Range("A" & Rows.count).End(xlUp).row This will give you the last used row even if there are blank rows in your data
    rwOriginalMax = wsOriginal.Range("A1").CurrentRegion.Rows.Count
    rwInterpolMax = wsInterpol.Range("A1").CurrentRegion.Rows.Count
    'These are selecting data from A1 to E and going to the last row before the first blank row
    arOriginal = wsOriginal.Range("A1:E" & rwOriginalMax)
    arInterpolData = wsInterpol.Range("A1:B" & rwInterpolMax)
    'This is clearing any content from range K2 through O and the last row before any blank row
    wsInterpol.Range("K2:O" & rwInterpolMax).ClearContents
    'This is collecting all the rows that were just cleared plus row 1 at the top
    arInterpolResult = wsInterpol.Range("K1:O" & rwInterpolMax)
    'beginning at 2 and going to the last row number before the first blank row on the Interpolation sheet
    For rwInterpol = 2 To rwInterpolMax
    'beginning at 2 and going to the last row number before the first blank row on the Original sheet
        For rwOriginal = 2 To rwOriginalMax
            'comparing the absolute value of, the numbers on the Interpolation sheet rounded to 3 decimals - the numbers on the Original sheet
            'to see if the result is less than or equal to .02 in columns 1 and 2 in the array made from the ranges of collected data
            If Abs(Round(arInterpolData(rwInterpol, 1), 3) - arOriginal(rwOriginal, 1)) <= Limit _
             And Abs(Round(arInterpolData(rwInterpol, 2), 3) - arOriginal(rwOriginal, 2)) <= Limit Then
             'If they are then updating the 1,2,3,5 columns of the Interpolation array to match the Original array
                arInterpolResult(rwInterpol, 1) = arOriginal(rwOriginal, 1)
                arInterpolResult(rwInterpol, 2) = arOriginal(rwOriginal, 2)
                arInterpolResult(rwInterpol, 3) = arOriginal(rwOriginal, 3)
                arInterpolResult(rwInterpol, 5) = arOriginal(rwOriginal, 5)
                Exit For
            End If
        Next rwOriginal
    Next rwInterpol
    'Putting the results left in the Interpolation array into the range K1 through O and the last row before any blank row
    wsInterpol.Range("K1:O" & rwInterpolMax) = arInterpolResult
End Sub

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