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Detecting automation

The words not a robot is written in wavy text, the word not is written underneath in regular text.


Setting challenges that are quick for users to complete but hard to automate. This prevents automated access. For example, when filling in a survey a user has to complete a challenge before submitting their answers, like reading distorted text or identifying objects in a photo.


  • Reduces impact of automated access to systems, such as denial of service or spam
  • Modern detection mechanisms take place without challenges for the user to complete


  • Computers are able to complete some challenges due to progress in machine learning or the feasibility of building click-farms
  • People using assistive technologies may be prevented from completing challenges
  • Large amounts of data are collected in order to build the engine for detecting automated access