Preventing website spam is essential to maintain the quality and integrity of your online platform. Here are several strategies and techniques you can use to stop website spam:

CAPTCHA: Implement CAPTCHA tests on your registration and comment forms to distinguish between humans and bots. Google's reCAPTCHA is a popular choice.
Use a Spam Filter: Utilize spam filters or plugins like Akismet (for WordPress) to automatically detect and block spam comments and submissions.
Moderation: Enable manual moderation for user-generated content. This way, nothing gets published without human review.
User Registration: Require users to register before they can comment or post content. This can deter many spammers.
Rate Limiting: Implement rate limiting on your forms to prevent a single user or IP address from making too many requests in a short period.
Blacklisting: Maintain a list of blacklisted IP addresses, domains, and keywords that are commonly associated with spam.
Content Filtering: Use content filtering to detect and block spammy keywords, URLs, or patterns in user-generated content.
Honeypot Fields: Add hidden fields to your forms that only bots can see. If these fields are filled out, you can automatically mark the submission as spam.
User Verification: Require users to verify their email addresses or phone numbers during the registration process.
SSL Encryption: Use SSL encryption to secure your website and make it harder for automated bots to interact with it.
Comment Whitelisting: Allow comments or content only from approved users or trusted sources.
Utilize Web Application Firewall (WAF): WAFs can protect your site from various types of malicious activity, including spam attacks.
Educate Users: Educate your community about spam and encourage them to report it. Many platforms allow users to flag spam content.
Update Software: Keep your website software, plugins, and themes up to date, as outdated software can have vulnerabilities that spammers exploit.
IP Blocking: Consider blocking specific IP addresses or IP ranges known for spammy activities.
Analyze Traffic: Monitor your website's traffic for unusual or suspicious behavior and patterns.
Feedback Loops: Set up feedback loops with ISPs and email providers to help identify and prevent email spam.
Implement DNSBLs: Use DNS-based blackhole lists to block known spam IP addresses.
.htaccess Rules: You can create rules in your .htaccess file to restrict access from certain IP addresses or user agents.
Content Policy: Clearly define and communicate your website's content policy, and enforce it consistently.
Stay Informed: Keep up with the latest spam tactics and technologies to adjust your defenses accordingly.

Remember that no method is entirely foolproof, and spammers are continually evolving their tactics. A combination of these strategies and regular updates to your spam prevention measures will help you effectively stop website spam.

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