(a) When did “Pong” come out? (I WAG 1979.) And (b), at that time, did video arcades exist? In other words, was Pong the first of its kind, or just the first non coin-operated video game?
when in doubt, try wiki.
IIRC there were pinball/pool arcades that may have had other games of chance/skill. I believe these were usually referred to as “pool halls” though. I think the term “arcade” usually only applied to amusement parks until video games became popular (late 70’s/early 80’s). The first video games were mainly in bars and convenience stores. As the games became more popular, they cropped up in more places (department store lobbies), until there were arcades that had nothing but video games. That just exploded. Just in my little corner of suburban Pittsburgh, in the mid 80’s we had something like 5-6 arcades going at one time, and probably nother 7-8 stores that had between 2 and 5 games . Not many of them lasted long, and by the late 80’s/early 90’s, arcades were something you only saw at the malls, and they mostly had fighting, racing and light gun shooting games. Eventually even those died out.
People say the home systems killed arcades. I don’t buy that. In my area, the cops used to raid the arcades pretty frequently, they were seen as trouble spots for drugs and underage drinking. I believe some of the arcade owners were pressured by the police/local politicians into shutting down, others decided the fights, damage to machines, and legal troubles just wasn’t worth the hassle of squeaking out barely enough quarters to pay the bills (arcade machines use a lot of juice and can be expensive to repair if you can’t do it yourself).
Whatever the reason for it, the decline of arcades led to fewer new machines being made. They started focusing on fewer but really expensive machines like driving games with cockpits or jet ski games that you could sit on and move back and forth to steer. Those died out too, and the arcade, which stopped Japan’s economy at one point (they ran out of the coins used in the machines), came to an end.
Wiki has a lot of information, but some of your questions aren’t immediately answered by the Pong page.
(a) Pong began life as a coin-operated video arcade game, and it debuted in late 1972. The home version was first sold in 1975 as the Sears Tele-Games Pong, and Atari-branded home Pong units came in 1976.
However, Pong was based on the Table Tennis game on the Magnavox Odyssey home console, which was prototyped in 1968 and eventually marketed in early 1972.
(b) Amusement arcades have existed since at least the 1920s (think pinball machines, billiard tables, bowlers, cranes, etc.), and some may have had video arcade games in 1972. Computer Space, the first commercial video arcade game, was released in late 1971. (Computer Recreation’s The Galaxy Game debuted first in early 1971, but was not commercially released; its only location was Stanford University.) A clone of Computer Space called Star Trek by a company called For-Play was in limited distribution in mid-1972.
No only-video arcades would have existed at the time, though; pinball was king in arcades until at least the late 1970s (and most arcades kept at least a few on-hand through the 1990s), and there were too few video coin-op machines in 1972 to fill an arcade.
“was Pong the first of its kind, or just the first non coin-operated video game”: No and no.
The arcade Pong was the third video arcade game (not counting clones), and the home version was the second released home console. (Ralph Baer, the man who prototyped the above-mentioned Magnavox Odyssey, had a number of complete and commercially-viable video game products prototyped before Pong; early games were playable in 1966.)
As the information was posted already, this thread just needs a trip down memory line:
Video Games Live
With Pong as the opening act no less.
We had the Pong game, as a Christmas Present, I believe, probably from Sears, since I seem to recall having it in about the 1975 time frame. Forced my father to buy a whole new TV it did, since the old B&W had to be used for the Pong game. 
Back in the early 70s, you played in places that had collections of pinball games. But it was more likely that the pinball games were limited to 3 or 4 that were owned by something like the bowling alley, or a small grocery store, or the like. I remember playing pinball in an enclosed “arcade” area with about 4 of them at the Albuquerque airport in the summer of 1973. Almost missed getting back on my flight from Wichita to LAX as a result. :eek: