Blockchain is a system of recording information in a way that it is not possible to change, hack, or cheat the system. Our data will be more secure using this technology. Blockchain is a type of DLT (Distributed Leger Technology) in which transactions are recorded with an immutable cryptographic signature called a hash. It helps to reduce risk, stamps out fraud and brings transparency in scalable ways. Block chain consists of three important concepts: blocks, nodes and miners. Blockchain concept is similar or in simple ways like google docs where all the users can use the same document in sharing and update the changes in real time transparently. Similarly, it provides distributed access. Blockchain technology has practical applications in financial industry, smart contracts, Digital IDs, Internet of things etc. also it is used to secure sharing of medical data, cross-border payments, cryptocurrency exchange real estate processing platform etc. So, blockchain is very useful and beneficial latest technology.