php - When to go for a library file in codeigniter -

php - When to go for a library file in codeigniter -

i utilize controller files project. confused when create libraries. can please allow me know when create libraries files , purpose?

i can define following:

controller: entry point of application associated uri.

helper: helpers written in procedural format rather oop format. little scale tweaking handled this. name suggest helper file helps main application controllers in ways.

library: libraries conventionally reusable code can used on different projects.

so if want write library should reusable , generic. or waste of time , effort.

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