dApps is short for Decentralised Applications. Most readers will be familiar with modern day applications, such as the Microsoft Office suite or Instagram on their phone. These applications are what the vast majority of developers have created, centralised applications.
Centralised software is directly controlled by a single entity. Users are relying upon this single entity to send and receive information safely, whilst maintaining privacy to others users in the system. At present the dApp world is still evolving as it has followed on from the explosion in blockchain and cryptocurrency technology. It is generally considered that a dApp is an application that has no central point of failure. No single server or location storing all information and processing.
An example of using decentralised applications is within Ethereum. We can use ‘smart contracts’ to create legal contracts hosted in a decentralised manner on the Ethereum blockchain; amongst a myriad of other potential use cases.