The term software describes programmes that run on hardware devices. Software combines three essential concepts that are all data-based: calculation, communication, and storage.
Open data refers to freely accessible, usable, modifiable and shareable data that anyone can use for any purpose. The term is usually used for public sector information.
Open-source software can be described as computer software (programmes) that can be used, modified and distributed free of charge.
A simple explanation of the term data is to see data as symbols containing information. These symbols are interpreted by the recipients of the data.
Algorithms are basically step-by-step instructions converting inputs into output. The written recording of the algorithms that makes it possible for computers to execute them is called a programme or software.