While there are almost as many definitions of history as there are historians, modern practice most closely conforms to one that sees history as the attempt to recreate and explain the significant events of the past. Caught in the web of its own time and place, each generation of historians determines anew what is significant for it in the past. In this search the evidence found is always incomplete and scattered; it is also frequently partial or partisan. The irony of the historians' craft is that its practitioners always know that their efforts are but contributions to an unending process.
Interest in historical methods has arisen less through external challenge to the validity of history as an intellectual discipline and more from internal quarrels among historians themselves. While history once revered its affinity to literature and philosophy, the emerging social sciences seemed to afford greater opportunities for asking new questions and providing rewarding approaches to an understanding of the past. Social science methodologies had to be adapted to a discipline governed by the primacy of historical sources rather than the imperatives of the contemporary world.

The laptop computer is a small, portable computer that's light and small enough to hold on your lap. It is smaller than a luggage but larger than a notebook computer. A laptop usually weighs between 8 and 14 pounds, and when folded shut is about the size of a small briefcase. Laptops can be plugged in or run on batteries, although the batteries must be recharged every few hours. Laptop computers use a thin, light weight display screen called a flat-panel display, rather than the cathode ray tube technology of larger personal computers. Laptop displays vary widely in quality. Typically, their display screens show fewer lines than displays on larger computers and can be difficult to read in bright light. Laptops are self-contained units, having their own CPUs, memory, and disk drives. A laptop can be ideal for the on-the-go user who needs a second, portable computer.