What Does Shortest Path Mean in the Six Degrees of Wikipedia Game?

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In the Six Degrees of Wikipedia game, the shortest path is the smallest number of hyperlink clicks needed to get from one Wikipedia article to another. You start on a given page, follow only the links inside article text, and count each click as one step; the winning path is the one with the fewest steps. This definition applies to the game and to tools such as Six Degrees of Wikipedia, which searches Wikipedia's link network for the shortest hyperlinked route between two pages. It is a specific, clickable version of the general graph-theory idea of a shortest path.

The basic mechanics

Wikipedia articles form a directed graph: each article is a node, and each in-text hyperlink is an edge pointing from the article that contains it to the article it links to. A shortest path is a sequence of articles where every consecutive pair is connected by a real link, and no shorter sequence exists.

Two details matter in practice:

  • Direction counts. Links are one-way. A links to B does not mean B links back to A, so a path that works in one direction may not exist in the other.
  • Only article links count. Navigation elements, categories, references, and external links are not part of the in-text link graph used for path-finding.

A simple example: if the article "Banana" links directly to "Fruit," the path Banana → Fruit has length 1. If it does not, but Banana → Tropical fruit → Fruit exists, the shortest path is length 2 — unless some other article gives a one-click route.

Why short paths are common: six degrees of separation

Six degrees of separation is the idea that any two people are connected through a small chain of acquaintances. Wikipedia shows the same pattern in its link network: because articles are densely cross-linked, most pairs of pages are only a few clicks apart. A tool that searches for the shortest path is essentially testing that claim for a specific pair of articles — and often confirming it with a surprisingly small number.

This is why the game is interesting: the challenge is not whether a short path exists, but finding the shortest one, which usually means spotting a hub article (a country, a broad concept, a year, a profession) that links to many things at once.

How a shortest-path tool works

Six Degrees of Wikipedia describes itself as a way to "find the shortest hyperlinked paths between any two pages on Wikipedia." In use, the pattern is:

  1. Input: a starting article and a target article.
  2. Action: the tool traverses Wikipedia's link graph, expanding outward from the start page level by level and checking whether the target has been reached.
  3. Expected result: one or more paths, each shown as an ordered list of articles you could click through, with the shortest path first.

The level-by-level search is what guarantees "shortest": the first time the target appears, no shorter route can exist. Note that the site's page states it requires JavaScript, so the search runs in the browser and will not work with scripting disabled.

When no path or a surprising path appears

If a tool reports no route, or a route much longer than you expected, check these causes before assuming a bug:

  • Link direction. Try swapping start and target. A short path one way may be long or absent the other way.
  • Exact page titles. Redirects, alternate spellings, and similarly named articles can send the search to the wrong node. Confirm you are using the exact article title.
  • Recent edits. Wikipedia changes constantly; links added or removed since a path was recorded can break or shorten it.
  • Scope of links. If you are playing by hand, remember that only in-text links count — a connection you "know" exists may live in a template or category instead.

Graph theory vs. the game

In graph theory, a shortest path is any minimum-length route between two nodes in a graph, and algorithms such as breadth-first search find it for unweighted graphs. The Wikipedia game is a concrete instance of that problem: unweighted (every click costs 1), directed (links are one-way), and defined only over article hyperlinks. Keeping that mapping in mind helps: the game's rules are not arbitrary, they are the graph's structure made playable.