Why is everything backwards? LIFO vs FIFO

In computer programming, a stack is where one stores items of data in an order which is useful. Information is piled on a stack in one module and control is transferred to another module which pulls information off the stack (Input) to work on (Process) and when done returns the information processed to the stack (Output).

There are two kinds of stacks – LIFO and FIFO.

A FIFO stack is a “First In First Out” stack. An author begins a book or a sequence of posts and writes them in order, from first to last (First In). A reader begins with the first chapter and reads them in order from first to last (First Out). This stack functions like a queue and the programmer keeps track of two values (pointers) – the address location in memory of the first item (for output) and the address in memory of the last item (for input).

Most stacks in computer software are LIFO stacks. They operate like a stack of items. When input happens, items are piled on the stack one after another, on top of each other. Like a stack of paper. When retrieved for use, the Last In – the item on top – is the First Out. The only pointer the programmer needs to keep track of is the top item on the stack.

A blog is a LIFO stack … the last post written is at the top. It is the most recent. It should be the most timely for that reason. Older items of information that are less useful gradually become buried in the pile. They are still available but one needs do no additional work with them. A blog is never out of date because the most recent post is always on top.

If you want your material to be read in order from one point to another, however, this can be very frustrating … for example, your daily devotion based on the previous Sunday’s sermon. You want people to be able to read them in order. What can be done about this?

To summarize, a FIFO stack is a pile of papers stacked face down … you turn the stack over and begin with the first page. A LIFO stack is a pile of papers stacked face up – and therefore in reverse order … you begin reading the most recent item first, and then sequentially down through the stack to the first item. Which order – LIFO or FIFO – is most useful to your stack of posts?




“Technical Issues” is a category of posts prepared for “The Writing Pastor” workshop attempting to provide answers to questions that might come up related to the technical issues of blogging. I am not an expert … but willing to share my opinion and experience. Someone who knows what they are doing will probably find my generalizations hilarious. My hope is that someone who knows less than I do might find them helpful.

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