Google is introducing a new search service—strictly for computer programmers only.

The Web search leader said late on Wednesday it is introducing Google Code Search, a site that simplifies how software developers search for programming code to improve existing software or create new programs.

Google product manager Tom Stocky said the Mountain View, California-based company is set to help programmers sift through billions of lines of computer source code using its familiar search box to uncover snippets of reusable software.

"For a long time it has been sort of an unsolved problem," said Stocky, a product manager in the developer products group. "It is hard to find references to this sort of data," he said.

Google is applying the same machine-driven techniques it uses to help consumers search the Web for text, images, video and books to help professional programmers as well as computer enthusiasts overcome stumbling blocks to writing code.

Searchers can seek out specific programming terms or computer languages and dive deep into compressed code to locate specific features. Users also can narrow a search to find software code based on specific licensing requirements, which is a big deal in warding off future patent litigation.

Similar to how a consumer might type a few words into a standard Google search box to find an answer, programmers can seek out relevant lines of code at http://google.com/codesearch and find a range of search results that link them to answers.

It's just that the results are for machine-readable phrases like: "go{2}gle" "hello, world" or "^int printk."

It's commonplace, when looking to improve a particular line of software, for most code writers to search the Web for quick tips. But finding actual programming code rather than just discussions about a particular coding problem is tough.

To meet this need, special sites serving computer developers have sprung up that offer repositories of code. Most are small, typically require membership and are often devoted to only a specific class of software or problem.

Several software programmers say Google Code Search appears to answer some of the basic nightmares of building software by creating a single place where one can trawl through all the publicly available computer code in the world.

Google searches through code repositories that are popular among programmers -- CollabNet's Subversion and another alternative called CVS, Stocky said.

The service began as a way for Google programmers to search through internal company code. It added a search of publicly available code and then recently decided that it might as well open up the service to others.

The results that come back from searches on Google Code also link directly to the compressed data files in which programs are often stored.

"Instead of searching Web pages, developers are searching over billions of lines of actual code," Stocky said.

Initially, Google Code Search is advertising free. Should the site prove popular, Stocky said Google may consider running pay-per-click advertising along search results, the way it makes money from its more mainstream search services, he said.