Difference between a Standing and a Professional Army?

According to Wikipedia

A standing army is a permanent, often professional, army. It is composed of full-time soldiers (who may be either career soldiers or conscripts) and is not disbanded during times of peace. It differs from army reserves, who are enrolled for the long term, but activated only during wars or natural disasters, and temporary armies, which are raised from the civilian population only during a war or threat of war and disbanded once the war or threat is over. Standing armies tend to be better equipped, better trained, and better prepared for emergencies, defensive deterrence, and particularly, wars. The term dates from approximately 1600, although the phenomenon it describes is much older.

However they never say what exactly the difference between a professional and standing army is. I always assumed professional army meant an army full of career soldiers and not conscription based but apparently that’s what a standing army is.

Conscripts make a significant portion of the Israeli standing army even in peacetime. There can theoretically be a standing army which is not necessarily a professional army.

A Standing Army means: An Army which is available for use right now as opposed to being built up by recruiting when needed.

A Professional Army is one where the members are volunteers as opposed to conscripts/draftees*

In reality, almost all modern militaries, even ones with conscription/draft have a large cadre of long service professionals, senior to middle officers, career NCO’s, and some "long lead in training "posts like pilots. At the same time, almost every military has large reserve pools, some of which get called up for service during active operations and an Army in the middle of a major war will always expand in practice in light of additional responsibilities.

Professional militaries are more than just a volunteer one. It’s kind of a somewhat vague concept, but basically the idea is that the members, especially officers and NCOs are, and perceive themselves as members of a profession, much like say… doctors, lawyers, or other civilian professions. Part of this is concerned with being sort of self-regulating and self-advancing, in that the members are interested in furthering and self-policing their professions, and setting high expectations for their members.

Having some degree of volunteer military is a prerequisite to a professional military, but isn’t really the determining factor.

It all has to do with how the soldiers view their military service and jobs.

Conscripts usually only serve full-time for a relatively short period (say, 18 months to two years), and thereafter return to civilian life (possibly with some obligation to be available for refresher reserve training).

Professionals sign up for the long term, and do indeed see their service as a profession and a career: the services in the UK certainly make a great play in their recruitment advertising of the professional and technical training they offer for a range of careers. In the UK the shortest period of engagement for the army is 12 years, but they may be selected to go on for 24 or 30 years, up to a retirement age of 55.

So a standing army may have conscripts, but will have a core of professionals to train the new arrivals and keep things going; but a professional army will be composed only of people signed up for the medium to long term - and it has to look after them rather more carefully than they might for short-term conscripts.

Further to the above there is a difference between short service professional armies like the US (standard enlistment 4 years active) with long service ones like commonwealth (standard enlistment minimum 10+ years).

That’s very much the US Army’s take on the word professional. They don’t exclude reserve components or even DA civilians. There’s a proponent, The Center for The Army Profession and Ethic. There’s a doctrinal publication, ADRP-1 - The Army Profession. Required training was conducted as they rolled out the efforts to strengthen professionalism after over a decade at war.

From the page linked to where ADRP-1 can be downloaded: