Understanding Transaction Class Output in R?

Question

Would someone shed some light on the output if i run a summary of an object of class Transaction, with reference to association rule mining. For example:

transactions as itemMatrix in sparse format with
 510 rows (elements/itemsets/transactions) and
 8361 columns (items) and a density of 0.003117649 

most frequent items:
                               PREPACK CARROTS 1EACH HASS AVOCADO 1EACH. 2 AT 3.00 EACH. AVOCADOS 2 FOR 5 
                                                  54                                                   51 
                         COLES EGGS FR RANGE 700GRAM                              COLES DAIRY MILK 2LITRE 
                                                  41                                                   31 
                          DAIRY FARMERS DAIRY 2LITRE                                              (Other) 
                                                  29                                                13088 

element (itemset/transaction) length distribution:
sizes
 2  3  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 
 1  1  5  8  9  9 13 11 12 16 17 12 13 14 15 19 15 17 18 26 18 18 11  8 16 10  8 10 14 11  6  9  8  8  9  6 
39 40 41 42 43 44 45 47 48 49 50 51 52 53 54 56 57 58 59 62 63 64 68 69 72 73 74 78 81 86 87 
 7  6  5  2  8  4  5  4  2  2  4  5  1  3  2  4  6  4  2  2  1  1  1  1  1  1  1  1  1  1  1 

   Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
   2.00   16.00   23.00   26.07   34.00   87.00 

includes extended item information - examples:
  labels
1      1
2     10
3    100

The above is the output generated from my transaction data. I've read the R Documentation but what is the element (itemset/transaction) length distribution ? And the labels?

Thanks!