CUSTOM CONVERSION VARIABLES (eVars)
Often as people learn Site Catalyst, they confuse eVars with Events in Commerce, or they don’t understand when to use an s.prop and when to use an eVar.

First of all, the only thing that eVars really have in common with s.props is that they are both custom variables. Just as s.props are custom Traffic variables, eVars are custom Commerce variables. That about where the similarities end, however, as they are really two completely different animals, in terms of what kinds of information they give and how they function.

But the fact remains, just as with custom Traffic reports, that these custom Conversion eVars do give you custom information, allowing you to answer your custom questions for your chosen segments.

This is very important when considering segmentation because it allows you to segment your key visitors and measure how many of them complete any of your success events.

“Evars” or “eVars”?
As you see this Site Catalyst word in various locations, you will undoubtedly see both of these versions of the word. Both are correct, since it is not a real word anyway. However, where you will most commonly see the word is the code and in the reports. In code, you will see the latter capitalization: eVar. You will see code that looks like this:

      s.eVar1 = “x”;

However, when you look in the Site Catalyst interface, you will see the first version, or “Evar”. In the navigation of Site Catalyst under Conversion, you will see the folders entitled “Custom Evars 1- 10” or “Custom Evars 11-20,” etc.

This section uses the “eVar” spelling, because that is the one in the code, and it must be done that way in the code. When you are writing your emails or chatting, feel free to use either version.

HOW EVARS WORK
Unlike a traffic variable where you must set it on every page, conversion variables are persistent variables, and hold their value for longer than one page. How long they hold their value is decided in the Conversion Variable settings in the Admin Console. This way, you can measure them by the success events, or in other words, by conversion.

Conversion report are used to answer questions about what affected success, so the value is held in the eVar for a while to see if success happened. When a success event is completed, the credit for that success is given freely to any conversion variables that are still “alive”. That way the report for that conversion variable will show how much success came from each value.

      Page 1: Entry page -> Page 2: Log in -> Page N -> Conversion --->

s.eVar1=”Logged In”;

In the example above, you can see that on Page 2 a person logs in. That value of “Logged In” can be help indefinitely, to see if there is a conversion. When there is, the Logged In” status receives credit for one conversion. Remember, this conversion can be any success event, so by using these variables in this way, you could see things like registrations for logged in or not logged in, form completions by people who were logged in or not, revenue generated by people who were logged in or not.