You have likely added a postscript to the bottom of a handwritten note, an office memo, or an email without thinking much about it. Those two letters stand at the very end of our messages, signaling a final thought after the signature. But where did this habit come from, and why do postscripts continue to hold such a powerful psychological grip on readers?
The abbreviation PS stands for postscript, derived from the Latin phrase post scriptum, which literally translates to "written after." Historically, before word processors and typewriters made editing effortless, writers relied on pen and ink to compose correspondence on precious sheets of paper. If you forgot a crucial detail midway through drafting a letter, or if a new thought arrived just as you were sealing the envelope, starting over meant wasting an entire page. The postscript became the practical solution for adding last-minute information without rewriting the whole document.
Today, the postscript serves a much deeper purpose than mere convenience. In modern communication, including digital correspondence and marketing copy, the PS is often the most read part of the message. Understanding the mechanics behind this writing tool allows you to use it with intention, whether you're crafting a professional email, a cover letter, or a personal note.
The History and Evolution of the Postscript
Centuries ago, the physical constraints of paper production and mail delivery shaped how humans communicated. In the 18th and 19th centuries, paper was expensive, and ink was messy. Writers would often fill every square inch of a page—sometimes writing horizontally, then turning the paper sideways to write vertically across the existing lines in a practice called cross-hatching.
When a writer finished a letter, signed their name, and then realized they missed something important, they added a postscript at the bottom or along the margins. Over time, this functional workaround evolved into an accepted epistolary convention. Authors like Jane Austen and Charles Dickinson frequently used postscripts in their personal letters not just for forgotten news, but to inject personal intimacy, quick jokes, or affectionate sign-offs that felt too casual for the main body of the letter.
As typewriters emerged, adding text after the signature remained a deliberate formatting choice. Writers realized that breaking away from the formal structure of a letter created a distinct conversational shift. This shift signaled to the reader that the formal constraints had dropped away, inviting a more direct and candid voice.
Why the Postscript Commands Attention
Human reading habits follow predictable patterns. When someone opens a letter or scrolls through an email, their eyes rarely move in a steady, linear march from the first word to the last. Instead, our gaze tends to scan. We look at the sender's name, glance at the subject line or opening sentence, and frequently jump straight to the bottom to see who signed it and how it ends.
This natural scanning behavior gives the postscript an unfair advantage. Because the PS sits right at the visual finish line of your message, it catches the eye before the reader even dives into the middle paragraphs. Copywriters and direct-mail pioneers noticed this phenomenon decades ago. Figures like John Caples and Robert Collier discovered that readers often skip straight to the postscript to see the main takeaway or a special offer before reading the rest of the text.
When you place a thought in the postscript, you are placing it in prime real estate. Readers associate the bottom of a letter with summary, urgency, or personal candor. If you bury your most important call to action in the middle of a dense paragraph, it might get skimmed over. If you place a compelling reminder or a high-value takeaway in the PS, it punches through the noise.
Modern Uses in Professional and Personal Writing
The rules of communication shift constantly, but the postscript remains remarkably resilient. While you might not use it in a rigid corporate contract, it fits comfortably into many modern writing formats.
Email Outreach and Marketing
In professional email marketing, the postscript is a staple. Because subscribers skim promotional emails, marketers use the PS to deliver a final punchy reminder about a deadline, a discount code, or a primary benefit. For example, an email about a software update might end with: PS: This discount expires at midnight tonight, so make sure to claim your upgrade before then.
Cover Letters and Job Applications
Using a postscript in a cover letter can feel risky if handled clumsily, but it works wonderfully when used to highlight a specific, high-impact achievement that didn't fit neatly into the main narrative. It draws the hiring manager's eye back to your core value proposition right as they finish reading your application. PS: I recently built an open-source tool that automates the exact reporting workflow your team is hiring for; you can view it at GitHub.
Personal Correspondence
In personal letters or catch-up emails to friends, the postscript retains its original charm. It acts as a casual aside, a quick update on a pet or a hobby, or a warm expression of care that feels natural and unforced.
Common Mistakes When Using a Postscript
Writers sometimes misuse postscripts by treating them as an afterthought rather than a strategic tool. Avoid these frequent missteps:
- Burying critical information: Never hide the core instructions or the primary message of your entire document inside the postscript. The main body should always stand on its own.
- Writing an essay: A postscript should be brief—usually one or two sentences. If your PS spans multiple long paragraphs, it loses its punch and becomes confusing.
- Redundancy: Don't simply repeat word-for-word what you already stated in the introduction. The postscript should offer a new angle, a fresh reminder, or a distinct call to action.
- Overuse: If you add a postscript to every single email you send, it loses its special emphasis. Reserve it for messages where you want to highlight a specific point.
Extending Your Postscript Options: PPS and Beyond
Sometimes a single postscript isn't enough, which led to the creation of additional abbreviations. When you need to add yet another thought after the first postscript, you write PPS, which stands for post postscriptum (after the after-written).
While seeing a PPS occasionally adds a humorous, rambling charm to a personal letter, using multiple postscripts in a professional setting usually signals poor planning. If you find yourself writing a PPS, a PPS2, and beyond, take a step back and integrate those thoughts back into the main body of your message where they belong. Clear, concise organization always beats a cluttered cascade of footnotes.
Mastering the postscript is about understanding human psychology and visual flow. By treating the end of your message as an intentional landing zone rather than a dumping ground for forgotten details, you turn a simple formatting habit into a sharp communication tool.
Frequently Asked Questions
Is it acceptable to use a postscript in formal business emails?
Yes, as long as it remains brief and relevant. In professional communication, a postscript works best for highlighting a single deadline, a registration link, or an important logistics detail. Keep the tone professional and avoid using it for casual small talk.
Should I use periods in the abbreviation PS or P.S.?
Both versions are widely accepted. You can write PS without punctuation or P.S. with periods. Consistency matters more than the specific style choice, so pick one format and stick to it throughout your document.
Can I include a link inside a postscript?
Placing a link in a postscript is a common and effective practice, especially in digital marketing and newsletters. Because readers naturally scan to the bottom of a message, a hyperlink placed in the PS often generates high click-through rates.
What is the difference between a postscript and a footnote?
A postscript is a message or thought added after the letter's signature, written from the author to the reader. A footnote, by contrast, is a reference, citation, or explanatory note placed at the very bottom of a page or document layout to credit a source or clarify a technical term.
