From Rosetta Code
This example is in need of improvement.

Use this message box template when an example meets the task requirements, but could be improved in some way. If the example does not meet the task requirements, use Template:incorrect instead.

Insert this message above a programming example using the text {{improve|lang|Explanation of the problem.}}, where lang is the programming language used. This will put the page in Category:Examples needing attention and Category:Lang examples needing attention, and apply Property:example requires attention.

This is a template. There are many others. See Category:RCTemplates for a complete list of templates.