Top posting is the practice of placing the reply text to an email at the top of the message being returned, with the original message quoted below. Although most mail clients encourage top posting by automatically placing the cursor at the beginning of the message editor, the practice is often considered rude and against the rules of netiquette. In fact, RFC 1855 specifically states that the quoted message be above the reply text (and trimmed appropriately). While not binding, the RFC conventions are considered the de-facto standard in netiquette and non-compliance is regarded as arrogant and rude in many veteran Internet communities.
Although most experienced Internet users are in agreement regarding the issue of top posting, there remains a small percentage of users who prefer top posting, and insist on using it even at the expense of their peers. Some argue that top posting is better than bottom posting because the entire mail message is included below for reference. Indeed, there are certain environments in which top posting may be preferable for this very reason, such as customer service tickets. A good customer service reply should include all the necessary information stated as facts independent of appended texts. Therefore, as these replies by definition are not answering the questions asked one-by-one, having the full quote available for reference below the reply is desirable.
Arguments given against top posting include the fact that top posted replies include not only the text of the original email, but also any signatures attached. This can consist of up to six lines of text, including advertisements. Also, as top posted repliers rarely trim the quoted text, the quote can grow to many levels of replies, including a "footer trail" at the end. Extending this argument, when the quote character (usually the > sign) count makes the lines of text longer than the maximum the lines wrap, making the text unreadable. Another common argument is that these unchecked quotes waste bandwidth and storage space, and additionally muddle archive searches. However, probably the most common argument against the practice of top posting is easily summarized such:
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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