Welcome to you,
You may just have found about Scirra's creation tools and are considering using them to make your future application/game. Nevertheless, this is a new world for you, you might be a bit lost.
Let me help you a bit.
A - Construct-Classic/Construct 2: different tools, same methods
Construct-Classic Events Sheet
Construct 2 Events Sheet
Indeed, both Construct-Classic (CC) and Construct 2 (C2) looks very alike. They share the same event sheets system that allows you to visually and logically "code" your application. It's like puting together english sentences and the layout let you have a visual representation of what your application will look like.
Yet there are big differences between the two.
+ For example CC project files can't be opened in C2 (and vice versa).
+ CC file format is only .cap whereas C2 offers to save your project as a single file (.capx) or as a project folder (.caproj and a folder containing each events sheets and parts of your application)
+ Another major difference between CC and C2 is the exported file format.
Construct-Classic is designed to export exectuable files (.exe) relying on DirectX 9.c (windows 7 users need to manually install DirectX 9.c even if they already have DirectX11 and more installed) for the graphical display and hardware accelerated features and VC+ runtime library (DLLs that needs also to be installed).
CC will allow you on export to make an installer containing the installer for DirectX 9.c and the VC+ runtime library.
This means that CC will only make applications designed to be executed on Windows operating systems.
+ On the other hand, C2 exports HTML5 application. You will have a folder containing a .html file and a .js file. Depending on your export configuration you might also have a folder containing the assets of your game.
This file will have to be webhosted for your game to be playable. C2 integrates a local web server for your previews needs. You'll be able to test your applications in your browser without trouble.
° From R63 (a release from the 17th October 2011), C2 allows you to publish exported projects to the Google Chrome Web Store. See this tutorial on publishing to the Chrome Web Store for more information
° From R65 (a release from the 29th October 2011), C2 allows to export to iOS, Android, Symbian, Blackberry and webOS through the PhoneGap Build service. The feature is still experimental, be warned.
Learn more about making native phone apps with Construct 2 and PhoneGap.
° From R103 (a stable release from the 11th September 2012), C2 allows export to iOS and Android (through the wrappers appMobi and CocoonJS) in a stable way, and allows for .exe exporting through the wrapper Awseomium. It even can export windows 8 app.
° From R116, C2 lets you export Desktop apps for Windows, Mac, and Linux using Node-Webkit. However, Linux export may have graphics driver issues on some computers as of this release.
Other exporters not listed here are available too, and treated in the tutorials part of the website.
Scirra still focuses on HTML5 with regular releases with new features and/or bugfixes.
+ Construct-Classic has been around for longer than C2 of course and have undergone quite a lot of versions. The actual version of CC is "release r2".
CC came to "rX" versioning when Scirra left the community in charge of the maintenance of Construct-Classic (when Scirra focused on C2's development). At that time the software was known as "Construct v0.99.96".