1) Data is distinct pieces of information, usually formatted in a special way. All software is divided into two general categories:data and programs. Programs are collections of instructions for manipulating data.
Data can exist in a variety of forms -- as numbers or text on pieces of paper, as bits and bytes stored in electronic memory, or as facts stored in a person's mind.
Strictly speaking, data is the plural of datum, a single piece of information. In practice, however, people use data as both the singular and plural form of the word.