The 21st Century workplace isn't any different from the amphitheaters of ancient Rome.

You are fighting someone brandishing a tech skill in demand, or running to barely stay ahead of the corporate lion going cutting edge. There is no war here – it's a battle every day.

The great thing is that you will not end up as vulture feed. The Roman arena was a prison. The 21st Century workplace sets you free with multiple gates of learning. Online learning is a disruptive technology whose time has come. Even though, there are genuine criticisms against the effectiveness of massive online open courses, they have opened up ways for you to upgrade your skills at your own pace. This is the age of learning, and these seven online course sites help you dip into the pool of the latest technology and add some arrows to your quiver of tech skills.

It's not only about learning programming languages, but also the little unnoticed tech skills that could take you further in your career. Class is in session.

MIT OpenCourseware

MIT OpenCourseware

The Massachusetts Institute of Technology (MIT) was one of the pioneers of the MOOC movement and it remains one of the big pushers behind it. The century old institution has been the birthing ground for many technological innovations. MIT launched OpenCourseware in 2001 and opened up its undergraduate and post-graduate course materials online for free. Materials include syllabus, class notes, presentation slides, lecture videos, homework problems, and downloads. Nearly 280 organizations followed MIT's lead thus forming the Open Courseware Consortium. But more on that later.

MIT OpenCourseware has a friendly navigable system and you can search for technology courses going by Topic, Course Number, or Department. To dive deep, also try the Advanced Search.

Courses you can try: MIT OpenCourseware is a treasure trove of 2150 courses across disciplines. Some of the most visited courses are related to computer science – e.g. If you want to get into Android development, the Introduction to Programming in Java is a good place to start. You will also find OCW Scholar courses that are designed for independent learners who have few additional resources available to them. These are more complete packages and the one on Introduction to Computer Science and Programming is suitable for beginners.

Recognition: MIT OpenCourseWare is a publication of the course materials that support the dynamic classroom interactions of an MIT education; it is not a degree-granting or credit-bearing initiative.

Coursera

We have always followed the development of Coursera closely and Tina's article on Coursera courses to improve yourself & your career shows the breadth they have. Coursera offers 642 courses on its menu and most of them are asynchronous -- you have to enroll for the courses and learn along in your own time (within the timeframe of the course).

Head to the Courses page and search by course name, category, university, or instructor. Sign up on Coursera and enroll for your class. Coursera courses are time-bound, so you have to enroll for the sessions when the classes begin.

Courses you can try: To upgrade your tech skills, try out the specialization courses on Cybersecurity or Mobile Cloud Computing with Android.

Recognition: Coursera offers two types of certificates. Some courses offer a Statement of Accomplishment or a Verified Certificate for students who meet the course passing criteria. Nearly all courses offer a Statement of Accomplishment. Verified Certificates are awarded to students who take a course in the Signature Track. Signature Track courses entail a fee but it is an authenticated certificate that strictly proves that you completed the course by meeting all criteria.

Please note that neither Statements of Accomplishment nor Verified Certificates represent college credit from the university offering the course. They are simply Coursera's acknowledgement that you have completed the course.

edX

edX is a natural extension of MIT's open lectures. The large MOOC platform was started by MIT and Harvard University in 2012 and now include 47 other institutions like Berkeley, CalTech, and Cornell that offer free classes online. edX is open to everyone around the globe and all you need is a browser. Try the edX Demo to get a feel of the learning experience before you plunge deeper into the courses.

Browse through the Course list and pick a technical course that strikes your fancy.

Courses you can try: Computer Science is an entire discipline within edX. There are nearly 33 courses on offer. You can start with Introduction to Computer Science from Berkeley if you are a beginner or hit Introduction to Computer Programming from IIT Bombay if you want to grasp the basics. The selection of computer science courses seems small and narrow but there is a XSeries course on Foundations of Computer Science that is comprehensively packaged. XSeries courses are fee-based courses.

Recognition: Some courses have a fee for verified certificates but are free to audit. Others offer a free honor code certificate to anyone who meets the completion requirements.

Udacity

The hallmark of Udacity which makes it stand apart from the above offerings is that it is completely focused on computer sciences. But then, unlike the others it is a for-profit educational platform. Udacity offers cutting edge courses with the help of technology partners like Google and nVidia among others. All Udacity courses are free to enroll, but a subscription opens up access to projects, code-review and feedback, a personal Coach, and verified certificates. You can enroll anytime of the year and upgrade your tech skills with the free courses, but joining the paid program helps to sharpen the axe.

All courses are neatly arranged in a Course Catalog.

Courses you can try: Any according to the tech skills you need. Courses are summarized in detail with minimum requirements and organized into beginner, intermediate, and advanced levels.

Recognition: Udacity issues verified certificates when the subscription courses are completed. All courses have a final exam. Udacity says it follows a rigorous process to ensure academic integrity and provide value to the certificate.

Codecademy

Learn coding at Codeacademy

Learning to code is a basic tech skill, and if you want to do it interactively then Codecademy is a good place to hone your programming skills. The online learning community helps you learn coding while you build small 'n simple projects. Codecademy is completely free to use.

Explore all tracks from the Learn page.

Courses you can try: HTML/CSS, JavaScript, PHP, Python, Ruby, APIs.

Recognition: Codecademy does not offer any completion certificates or acknowledgements. It is just a platform that helps you get your feet wet in the language of choice. Codecademy may not be the place to get fully skilled, but it could help you get an idea where your passion lies.

Treehouse

Treehouse offers learning "tracks" that guide you towards mastery in topics like web design and development, WordPress, Android and iOS development, entrepreneurship etc. The site takes you through programming courses with video, quizzes, and some gamification. Treehouse follows a paid model – with a Basic course ($25/month) and a Pro course ($49/month). You can try it out on a 14-day free trial.

Learning is project based. Treehouse organizes all the courses in Tracks.

Courses you can try: Web Design, Web Development, Rails Development, PHP Development, iOS Development, Android Development, WordPress Development, Starting a Business.

Recognition: Treehouse does not offer completion certificates but relies on an assessment model with badges to indicate proficiency. Badges are just meant for motivation and have no real-world value. According to the site, they have a job board and a placement team that tries to find positions for those who complete the course. Badges and performance on the course are considered.

Grovo

Learn Tech Skills at Grovo

Grovo covers 130+ sites, apps and topics. The online learning platform covers them all with approximately 4500 "How-to" video lessons which you can digest in a minute or so. It calls itself "the world's quickest and simples learning company". Grovo has a freemium model, but if you are looking to grasp Internet tools and Web apps quickly, then give Grovo a try. The subscription starts from $15 per month but you can check the pricing chart for a more suitable one.

Lessons are organized into Tracks.

Courses you can try: Think of a tool and you will find a how-to here. From social media to 800+ lessons in project management & collaboration, there's a lot you can learn on the microlearning site if you are short on time.

Recognition: Grovo also follows a gamified model with badges to indicate performance.

The Good News -- There Are Many Many More...

The online learning tree is fortunately evergreen and dense. Shake the trunk and courses fall into your lap like ripened apples. Some go by with names like General Assembly, Lynda.com, and even W3Schools. One of the easier ways to search for a tech skill you want to work on is through a search engine. Here are five you can try immediately.

I had taken a deeper look into three of these search engines for online courses before.

Are You Upgrading Your Tech Skills?

The important question is – how? Does your company have an in-house program? Are you being sponsored to study outside? Or are you relying on your own hard work and maybe one of these online learning sites? Tell us about your trials and tribulations – and your success stories if upgraded tech knowledge helped you get a better cubicle in the office or grab that coveted project.

Image Credit: Thomas Leuthard