# Blocklist A blocklist is a list of items, such as email addresses or IP addresses, that are considered undesirable or untrustworthy. Blocklist are commonly used to block unwanted emails, prevent access to certain websites, or block certain types of network traffic. One common use of blocklist is in email systems, where a Blocklist is a list of email addresses or domains that are known to send spam or malicious emails. Email servers can use blacklists to identify and block emails from these sources, helping to protect users from receiving unwanted or potentially harmful emails. Blocklist may also be used to block access to certain websites or types of content. For example, an organization may maintain a blocklist of websites that are known to host inappropriate or malicious content, and use this blacklist to block access to these sites from their network. Blocklist may be maintained by organizations or individuals, and may be shared with others to help identify and block unwanted or untrustworthy items. However, it is important to note that blocklist are not always accurate or up-to-date, and some items may be mistakenly added to a blocklist or remain on a blocklist after the issue that led to their inclusion has been resolved. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.smtpd.dev/master/faq/email-deliverability/blocklist.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.