bangbang sends out bangs in sequential order from right to left, making it easy to guarantee the order of operations without having to worry about how your patch is laid out. This can be very helpful to avoid creating problems that might can arise when rearranging a patch and also for maintaining a clear patching structure. Trigger takes one argument <int> for the number of outlets you want.
Max Basic Tutorial 5: Message Order and Debugging shows how you can use bangbang to force output order of events, regardless of the spatial layout of objects within a patch. The bangbang object is similar to trigger, but all input is converted to bangs.
The object name can be abbreviated to "b".
In cases where you want to sequence specific symbols or values instead of just bangs, you can use the trigger object. You can also use bangbang in these situations by adding a few other objects.
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