Editing Rocket engine (section)

==Terminology==
Here, "rocket" is used as an abbreviation for "rocket engine".

'''[[Thermal rocket]]s''' use an inert propellant, heated by electricity ([[electrothermal propulsion]]) or a nuclear reactor ([[nuclear thermal rocket]]).

'''Chemical rockets''' are powered by [[exothermic]] [[redox chemistry|reduction-oxidation]] chemical reactions of the propellant:

*'''[[Solid-fuel rocket]]s''' (or '''solid-propellant rockets''' or '''motors''') are chemical rockets which use propellant in a [[solid|solid state]].
*'''[[Liquid-propellant rocket]]s''' use one or more propellants in a [[liquid state]] fed from tanks.
*'''[[Hybrid rocket]]s''' use a solid propellant in the combustion chamber, to which a second liquid or gas [[oxidizing agent|oxidiser]] or propellant is added to permit combustion.
*'''[[Monopropellant rocket]]s''' use a single propellant decomposed by a [[catalyst]]. The most common monopropellants are [[hydrazine]] and [[hydrogen peroxide]].