Thinking about getting into development, but are worried your programming skills aren’t quite good enough? If the answer is Yes, then Trailhead might be perfect for you!
Trailhead has been setup by Salesforce.com, inc to help developers and administrators at all levels. It provides an easier way of learning Salesforce development, whilst giving individuals the chance to test their knowledge on the platform.
This highly interactive tool contains the essential development elements of the Salesforce1 Platform. And by using gamification, which is built in to the tool, it rewards users for their achievements, by giving them the opportunity to gain points and badges.
Advanced developers need not feel left out though, as users can change the learning experience to fit in with their level of skill, therefore keeping the learning experience fresh and relevant. 
Other features of Trailhead include:
- Components that take you through various learning objectives of the Salesforce1 Platform in order to strengthen the learning goals.
- Test modules which you can take for every aspect of using the Salesforce1 Platform – when you pass it, you know you can do it!
- Self-paced, online learning
- You can earn points and badges when you complete units and modules, which show up on your profile – so everyone can see how you are progressing.
Get Trailhead now: https://developer.salesforce.com/trailhead