As briefly as possible, the Blockchain is a continuous sequential chain of blocks containing information, built according to certain rules. Blokchan as an eternal digital distributed log of economic transactions, which can be programmed to record not only financial transactions, but also virtually everything that has value.
But such a definition does not provide sufficient understanding of what it is and how it works. Consider the blockade in more detail and try simply and intelligibly to explain what kind of technology it is.
By allowing digital information to be distributed, but not copied, the technology of the block system created the basis for a new kind of Internet. The technology was originally developed for the digital currency, bitcoin, but now the technical community is looking for other potential uses for this technology.