Future Methods #inSalesforce

Future Methods #inSalesforce

This runs in the background, asynchronously. You can call a future method for executing long-running operations, such as callouts to external Web services or any operation you’d like to run in its own thread, on its own time.

Example:

Public class activateAccount{
    @future
    Public Static void updateAccount(List<Id> accountIds, Boolean active, String descptn){
        List<Account> accounts = [Select id,Active__c,Description from Account where Id IN :accountIds];
        for(Account a: accounts){
            a.Active__c= true;
            a.sampleDescription__c = descptn;
        }
        update accounts;
system.debug('!!!done!!!');
    }
}

In the anonymous window, try
List<Account> accounts = [Select id, Active__c, sampleDescription__c from Account];
List<Id> accountIds = new List<Id>();
for(Account a : accounts){
    accountIds.add(a.Id);
}
activateAccount.updateAccount(accountIds,true,'activatedAccount');

Reference: https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/apex_invoking_future_methods.htm