For things like hook, avatar, etc., check out this thread.
This glossary will grow, but for now just the basic stuff:
CPA - (sometimes known as Pay Per Action or PPA; also Cost Per Conversion).
CTA - Call to action. The part of your copy where you tell someone to do something (click a link, leave an email address, or buy....)
Copy - In the world of direct response (DR) copywriters, this is the text we use to sell product. It is meant to substitute a salesman that delivers (copy is cheaper - or so we believe.)
Downsell - If your client gets to the sales page (or the end of any sales funnel) and decides not to buy because of the price; you can offer him something cheaper, maybe smaller, and/or similar to the sold product/service (or maybe just anything that would be beneficial to your specific avatar) - this cheaper thing is called a downsell.
In some cases you can make a lot more money, because you are probably attracting different people to your offer anyways, and some of those people might not be able to afford the offer, but they might be able to afford the smaller cheaper thing...
DR - Direct Response (Marketing). This is different from your typical type of marketing. In direct response marketing your basically trying to get an immediate action (from the receiver of your ad) that can be tracked and tested. An action means usually to either click a link, leave your email address, or make a purchase.
This is usually different from branding (depending how you look at it), and "normal" marketing that is usually focused on design, beauty, and winning awards, but that doesn't usually track the ROI (return on investment) of the marketing campaigns.
DRM - Same as above.
HL - HeadLine (I've seen someone use it in this forum.)
LFSL - Long Form Sales Letter (A sales letter that is "long")
ROI - Return on investment. Basically means: how much money you get back in sales, after putting money into a specific "investment", in our case the investment is the ad or sales/marketing online/offline funnel.
SOS - Soup Opera Sequence (emails) - Just like a soap opera, people are waiting for the next part to come... SOS can also mean "Shiny Object Syndrome", which is another way of saying: Wasting money and time on "magic pills" that are supposedly going to make you rich fast, instead of focusing on doing the "right" work and starting to actually earn money.
Swipe - Or swipe file. Is a scan, pdf, doc file, etc., of an ad that has been proven to work. A lot of the good ones are from the times when there was no Internet, and everything had to be rigorously tested to make a profit after all the print and labor costs.
Modern savvy copywriters use these ads for inspiration. Sometimes you can actually swipe some words in the original ad and you have yourself a ready working one (the extreme of this is called plagiarism...), but more often (I hope) these are used for rewriting and inspiration. If we have a feeling our avatar is similar to the one in the specific swipe file, we can really benefit from reading and trying to understand why the ad worked, and then use these insights in our own copy.
Upsell - This is almost the opposite of the downsell. After a client has made the purchase, or during the purchase (like in the shopping cart - but be careful with this one.)
You can send him/her an additional offer (not always higher priced) and this way, again, you have a higher chance of making a bigger profit from the same (or similar) amount of time used in selling the first thing. It is known (which means I don't remember the specific research done ), that when people are in the buying mode, they tend to buy more, and the buying mode is especially strong after any purchase.
VSL - Video Sales Letter. These are usually put on landing pages, and are there to make you ultimately take action (and/or buy).
If you see something you don't understand in the forums, send me a private message or post under this post, and I'll try to get your answer as soon as possible.
Direct Response Dictionary
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