Google reCAPTCHA Keys User-based Review
Google's reCAPTCHA Keys offers a free service to your website safeguarding it from spam and abuse. Further, Google's reCAPTCHA Keys algorithm uses an advanced risk analysis engine and adaptive CAPTCHAs. In general, to keep automated software from engaging in abusive activities on your site. Moreover, it does this while letting your valid users pass through with ease.
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