Cannot understand meaning of integer ebayBatchesInProgress.get(0).get('batchesInQueue') in Salesforce?

I am trying to understand a class but cant understand meaning of (Integer)ebayBatchesInProgress.get(0).get('batchesInQueue') in the following program:

public static void ecommerceSyncMethod(){
        
        // Below executing a logic to judge the pre-queued batches :
        //For Ebay
        Integer numberOfBatchesNotProcessedEbay = 0;
        list<AggregateResult> ebayBatchesInProgress =  [Select Count(id) batchesInQueue
                                                        from AsyncApexJob 
                                                        where (ApexClass.Name = 'BatchToAddEcommerceItemEbay' 
                                                               OR ApexClass.Name = 'BatchToDelistEcommerceItem'
                                                               OR ApexClass.Name = 'BatchToUpdateEcommerceItem')
                                                        AND Status IN ('Holding','Holding1','Queued', 'Preparing', 'Processing')
                                                       ];
        
        if(null != ebayBatchesInProgress && !ebayBatchesInProgress.isEmpty()){
            numberOfBatchesNotProcessedEbay = (Integer)ebayBatchesInProgress.get(0).get('batchesInQueue');
        }
        
        //For Amazon
        Integer numberOfBatchesNotProcessedAmazon = 0;
        list<AggregateResult> amazonBatchesInProgress =  [Select Count(id) batchesInQueue
                                                          from AsyncApexJob 
                                                          where ApexClass.Name = 'BatchForEcommerceItemsAmazon' 
                                                          AND Status IN ('Holding','Holding1','Queued', 'Preparing', 'Processing')
                                                         ];
        
        if(null != amazonBatchesInProgress && !amazonBatchesInProgress.isEmpty()){
            numberOfBatchesNotProcessedAmazon = (Integer)amazonBatchesInProgress.get(0).get('batchesInQueue');
        }
        
        //For Watch Facts
        Integer numberOfBatchesNotProcessedWatchFacts = 0;
        list<AggregateResult> watchFactsBatchesInProgress =  [Select Count(id) batchesInQueue
                                                              from AsyncApexJob 
                                                              where (ApexClass.Name = 'BatchForEcommerceItemsWatchFacts' 
                                                                     OR ApexClass.Name = 'BatchToDeleteEcommerceItemWatchFacts')
                                                              AND Status IN ('Holding','Queued', 'Preparing', 'Processing')
                                                             ];
        
        if(null != watchFactsBatchesInProgress && !watchFactsBatchesInProgress.isEmpty()){
            numberOfBatchesNotProcessedWatchFacts = (Integer)watchFactsBatchesInProgress.get(0).get('batchesInQueue');
        }
        //For CrownAndCaliber
        Integer numberOfBatchesNotProcessedCrownAndCaliber = 0;
        list<AggregateResult> crownAndCaliberBatchesInProgress =  [Select Count(id) batchesInQueue
                                                                   from AsyncApexJob 
                                                                   where ApexClass.Name = 'BatchForEcommerceItemsCrownAndCaliber' 
                                                                   AND Status IN ('Holding','Queued', 'Preparing', 'Processing')
                                                                  ];
        
        if(null != crownAndCaliberBatchesInProgress && !crownAndCaliberBatchesInProgress.isEmpty()){
            numberOfBatchesNotProcessedCrownAndCaliber = (Integer)crownAndCaliberBatchesInProgress.get(0).get('batchesInQueue');
        }
        //For Shopify
        Integer numberOfBatchesNotProcessedShopify = 0;
        list<AggregateResult> shopifyBatchesInProgress =  [Select Count(id) batchesInQueue
                                                           from AsyncApexJob 
                                                           where ApexClass.Name = 'BatchForEcommerceItemsShopify' 
                                                           AND Status IN ('Holding','Queued', 'Preparing', 'Processing')
                                                          ];
        
        if(null != shopifyBatchesInProgress && !shopifyBatchesInProgress.isEmpty()){
            numberOfBatchesNotProcessedShopify = (Integer)shopifyBatchesInProgress.get(0).get('batchesInQueue');
        }
        
        //For Jomashop
        Integer numberOfBatchesNotProcessedJomashop = 0;
        list<AggregateResult> JomashopBatchesInProgress =  [Select Count(id) batchesInQueue
                                                            from AsyncApexJob 
                                                            where ApexClass.Name = 'BatchForEcommerceItemsJomashop' 
                                                            AND Status IN ('Holding','Queued', 'Preparing', 'Processing')
                                                           ];
        
        if(null != JomashopBatchesInProgress && !JomashopBatchesInProgress.isEmpty()){
            numberOfBatchesNotProcessedJomashop = (Integer)JomashopBatchesInProgress.get(0).get('batchesInQueue');
        }
        
        
        //Code to be executed when the schedule class wakes up
        map<id,list<Listing_Event__c>> mapOfProductAddVsListingEventEbay = new map<id,list<Listing_Event__c>>();
        
        map<id,list<Listing_Event__c>> mapOfProductUpdateVsListingEventEbay = new map<id,list<Listing_Event__c>>();
        
        map<id,list<Listing_Event__c>> mapOfProductRemoveVsListingEventEbay = new map<id,list<Listing_Event__c>>();
        
        
        map<id,list<Listing_Event__c>> listingIdVsEventListMapForEitherAddUpdateRemoveOrGetResult = new map<id,list<Listing_Event__c>>();
        map<id,list<Listing_Event__c>> listingIdVsEventListMapForAddUpdateRemoveOrGetResultWatchFacts = new map<id,list<Listing_Event__c>>();
        map<id,list<Listing_Event__c>> listingIdVsEventListMapForAddUpdateOrRemoveCrownAndCaliber = new map<id,list<Listing_Event__c>>();
        map<id,list<Listing_Event__c>> listingIdVsEventListMapForAddUpdateOrRemoveShopify = new map<id,list<Listing_Event__c>>();
        map<id,list<Listing_Event__c>> listingIdVsEventListMapForAddUpdateOrRemoveJomashop = new map<id,list<Listing_Event__c>>();