Questions

A bootstrap is the process of starting up a computer. It also refers to the program that initializes the operating system (OS) during start-up.

It referred to a bootstrap load button that was used to initiate a hardwired bootstrap program, or smaller program that executed a larger program such as the OS.

Because of its being pollution free and  combustion efficient, Hydrogen gas is  called fuel of future. Because of its origin in marshy places, Methane is called as 'Marsh Gas'.

Why Water Is Not an Element :

An element is a substance consisting of only one type of atom. Water consists of two types of atoms: hydrogen and oxygen.

water is both a molecule and a compound :

A compound forms whenever two or more atoms form chemical bonds with each other. The chemical formula for water is H2O, which means each molecule of water consists of one oxygen atom chemically bonded to two hydrogen atoms.

Thus, water is a compound.

It's also a molecule, which is any chemical species formed by two or more atoms chemically bonded to each other. The terms molecule and compound mean the same thing and can be used interchangeably.

Hence, water is both a molecule and a compound.