Setting up a Virtual Host is useful during web development so that you can easily access a running project via a custom, root level domain in your browser.
Insertion is a very simple and common sense approach to the sorting problem. It is stable, in-place, online, and efficient for small data sets and data sets that are already mostly sorted. Here we examine Insertion Sort in Ruby.
This tutorial is a step by step guide to setting up a basic Ruby/Rails and PHP web development environment from a fresh install of OSX 10.9 Mavericks.
Merge is a divide and conquer algorithm for sorting which is generally stable. Its average and worst case performance is O(n log n), which makes it more efficient than Insertion for most sets.
The Knapsack Problem is an NP combinatorial optimization problem in which items that have both value and weight are placed into a "knapsack" with a weight limit. Here a genetic algorithm is used to evolve good solutions.