An entity bean that can handle multiple simultaneous, interleaved, or nested invocations that will not interfere with each other.

An object that identifies an enterprise bean. A client can serialize the handle and then later deserialize it to obtain a

reference to the enterprise bean. What is home handle

An object that can be used to obtain a reference to the home interface. A home handle can be serialized and written to stable

storage and deserialized to obtain the reference.

A SAX parsing error is generally a validation error; in other words, it occurs when an XML document is not valid, although it

can also occur if the declaration specifies an XML version that the parser cannot handle. See also fatal error, warning.

Swapping: Whole process is moved from the swap device to the main memory for execution.Process size must be less than or equal to the available main memory.It is easier to implementation and overhead to the system.Swapping system does not handle the memory more flexibly as compated to the paging systems.
Paging:Only the required memory pages are moved to main memory from the swap device for execution. Process size does not matter. Gives the concept of the virtual memory.

It's how they handle failures. If the file is not found by require(), it will cause a fatal error and halt the execution of the script. If the file is not found by include(), a warning will be issued, but execution will continue.