Blockchain is one of the hottest topics in tech circles these days. With the rise in popularity of Bitcoin and other cryptocurrencies, as well as other smart devices that can utilize the technology, everyone wants to better understand how blockchain works.

But how to get started, and where to look? In order to determine which courses are best, it is first necessary to gain a basic understanding of what the options are and what is available online.

What are the best sources for online learning?

In general, there are several well-known sources for online learning and many more smaller ones. Depending on the subject, there are places that specialize in some areas more than others.

The first consideration is whether or not you are looking for a whole degree program. If so, there are certain schools that have become established leaders in degree courses, such as the University of Phoenix.

If what you are looking for is individual courses, there are a number of strong contenders among online institutions as massive open online courses (MOOCs) have been gaining popularity for several years now.

Some of the best known names are Coursera, Udemy, Codecademy, and The Great Courses. These sites offer open courses for audit given by some of the world's leading universities and specialists. In many of them, you can receive an official certificate of completion given by the hosting university that will give you credentials in the subject you've studied.

Blockchain - introductory components

What would an introduction to blockchain course consist of? Complete certificate courses generally include the following modules:

• Introduction to cryptography and cryptocurrency - In order to fully understand the use of blockchain, it is first necessary to gain an understanding of the fundamentals of cryptography and cryptocurrency. Cryptography is the technique by which crypted messages can be sent. What this means is that only the sender and recipient of a given message can access the information in a given message. Cryptography generally replaces letters with other types of code that cannot be read by most people.

Cryptocurrencies are types of money that utilize cryptography in their transactions. This includes Bitcoin, Ethereum, and others. They are essential to an understanding of blockchain because the most widespread usage of blockchain is in the calculation of cryptocurrency transactions.

• Introduction to ledgers - Ledgers are digital files that track the transactions in a blockchain.

Ledgers come in several different types. Distributed ledgers are ledgers controlled by all of the participants in a given transaction or set of transactions. They involve the use of multiple "nodes" or connection points linking data.

In a centralized ledger, there is only one node and one person controlling that node. Decentralized ledgers, which are utilized by Bitcoin and other cryptocurrencies, are networks of centralized ledgers.

Coursera offers a popular course introduction to blockchain through the Association for Certified Professional Accountants. The course offers all of the fundamentals to blockchain technology and cryptocurrency, and it will also lay out the benefits and drawbacks of using it. The average time of completion is 15.5 hours.

Specialty courses

Beyond these introductory courses, there are others that cover the basics of major cryptocurrencies such as Bitcoin and Ethereum, and how these currencies are utilized in blockchain technology. As mentioned on buidlbee, there are a lot of subtle aspects to the vagaries of these currencies and gaining a fundamental understanding of their nature is critical to being able to utilize them correctly in blockchain.

There are also courses available on becoming a blockchain developer. Blockchain developers build additional applications onto existing blockchain networks. These courses provide the basics of blockchain development, as well as introductions to Ethereum smart contracts, the various programming languages involved in blockchain development, and blockchain architecture. Udemy offers a popular course in this for a total of 24 hours of study.

There are also a number of more specialized blockchain courses. One of the popular ones now is blockchain for enterprise development.

In addition, there are courses that focus specifically on either the connection between blockchain and Bitcoin or blockchain and Ethereum, or both. One of the easiest and quickest of these is called Blockchain and Bitcoin Fundamentals offered by hackr.io, which can be completed in just three hours.

To learn the essentials of Ethereum and blockchain development, a good course to check out is Ethereum Blockchain Developer Bootcamp with Solidarity, offered by Udemy and involving an average completion time of 24 hours.

Advanced learning

If you're interested in even higher level learning, you might check out more advanced courses, such as MIT's Blockchain Technologies: Business Innovation and Application. Certified Blockchain Architect offered by the Blockchain Council is another higher-level course that you might look into once you've gotten the basics down.

If you're really excited about blockchain and want to make a career out of it, there are definitely options out there for you. Start by doing some basic research on the subject in general, then check out the course offerings on some of the more popular sites.