1. In general, contiguous refers to an object that is adjacent to another object.
2. When referring to a computer hard drive, contiguous or continuous refers to sectors on a disk that are by each other. When information is written to a disk if there is enough space the information is written contiguous. However, if there is not enough available sectors the data is written to multiple places on a disk causing it to be fragmented.
3. When referring to computer memory, contiguous refers to sections of memory that are next to one another.