The Internet giant announced that the purpose of the changes is to reduce the ranking of low-quality Web sites. For example, those sites not providing users with additional value, and which may include content simply copied from other websites, are considered not very useful.
More specifically, the changes aim to reduce what Google terms "webspam" -- a term designed to differentiate the problem from "email spam" -- whereby tactics such as 'keyword stuffing' frequently take place on websites. The idea is to ensure that sites on which keyword stuffing is taking place and where less emphasis has been placed on content value "above the fold" (on the visible pages themselves) are ranked lower than legitimate websites, raising the overall integrity and utility of the Web. This is simply a means of penalizing those websites which have breached Google's existing quality guidelines.
Google states it cannot risk providing details of the internal operating principles of the new algorithm to prevent certain websites from being altered to avoid detection. Simultaneously, the company advises webmasters to concentrate on creating high-quality sites with which users will be satisfied, and to continue guarding against spam on their Web pages.
Google has indicated that changes will be implemented simultaneously in all languages. We can expect this to be implemented over the next few days.