Electrical current is like the amount or volume of water flowing through the hose. An Ohm is the unit of measurement of the electrical resistance. A conductor like a piece of metal has its atoms so arranged that electrons can readily pass around the atoms with little friction or resistance. In a nonconductor or poor conductor, the atoms are so arranged as to greatly resist or impede the travel of the electrons. This resistance is similar to the friction of the hose against the water moving through it.
Resistance can cause heat and light Electrical resistance is essentially friction within the wire.
Just as friction can get something hot, so can the electrical resistance result in the wire getting warm or even hot enough to glow. The amount of heat is proportional to the diameter of the wire, its material and thus resistance, and the current. The thinner the wire, the more electrical resistance. This is because it is more difficult for the electrons to pass through the wire. The light bulb Tungsten wire is used in electric light bulbs because it has such a high resistance that a thin piece will glow white hot.