The New Blogger with the New Blogger template is a big improvement over the old classic template in many areas, including enabling bloggers who know nothing about HTML, CSS or Blogger tags to customize their blogs which they would be hard pressed to do with the old classic template. Plus there is no more "Republish" plus that sometimes forever spinning.
Now if you want to know whether you are having the old classic Blogger template or the New Blogger template, refer to the screenshot below:
Note that the top blog (Earn with Google AdSense) has a link LAYOUT circled in red. This blog is using the New Blogger template. For the second blog (Thur's template test blog), the link is TEMPLATE, also circled with a red ellipse. This blog uses the old classic template. Now I hope you know how to distinquish between old classic template and New Blogger template.
Backing up the New Blogger templateWhile there is a lot that I like about the New Blogger template, there is one big difference when you backup the template which irritates me. With the New Blogger template, when you backup the template, you also have to backup whatever Page Elements that you can backup (some like the Proflle, Archives, Link List, cannot be backup). The reason is, whenever you change New Blogger templates, some Page Elements will be deleted and some will become empty. Thus when you have backup Page Elements, you can easily put back in the missing or empty Page Elements. For more details, refer to Backup and change New Blogger template PLUS backup Page Elements or Backup and edit New Blogger template plus backup Page Elements
Backing up old classic Blogger templateBacking up the old classic template is a simple process. All you need to do is to sign into blogger.com (Dashboard), then click the TEMPLATE link (highlighted by a red ellipse in the screenshot above). This will bring you to the template editor. Click inside the template editor window, click ctrl+A to highlight all the codes in the template, click ctrl+C to copy the template, open an Notepad file, paste the template into Notepad, save the Notepad file in, say, a folder named "Templates" and preferably a sub-folder with the name of the blog if you have more than one blogs. Use a file name that gives as much information about the backup template as possible. Make full use of the possibility of using long filename. Name the backup template, for example, "Thur4s template test blog before expandable post summary hack 7 nov 07". In this way, if you ever need to use back any backup template, you will know which backup template to use.
The advantage here is, all the customizations (visitor counter, scripts for advertisements, search box, etc., are all incorporated into the backup template. There is no Page Elements to backup.