This was a topic I've been thinking about just today, and I think this is interesting to discuss. But when would you consider to be the official year where something stops being retro.

Personally I find the presence of the online world has changed the idea of "retro".

Funny you should mention this. Not too long ago, I noticed that Netflix had several shows that premiered between 2000 and 2010 listed under the category of "Retro TV." That surprised me a bit. I'm not sure where I would personally draw the line, but I could see the case being made that anything over 10 years ago (2007) could be considered retro.

At least 20 years old for retro. With some allowance to round out the decade, i.e. 1997 to 2017 20 year difference, so 90s are retro 1990-1999

At least 15 for me. Though 20 is ideal.

I know this has been beaten like a dead horse, but I'll chime in anyway.

I think things changed during and immediately after the '90s that made it hard to consider the following decade "retro". For one, we entered a new millennium. That in itself makes it difficult to see any post 1999 years as retro. Then there is the internet. It came into it's own in the mid-90s, and since the year 2000, it has evolved into such an important part of life. We almost can't conceive of a time with no online access to everything we ever wanted to know, watch, hear, etc. I still have difficulty considering anything about the internet "retro" with the exception of AOL and Geocities. I think it could be a while before we start thinking of any post 1999 years as retro.

The term retro as it applies to style and fashion refers to using furniture, accessories, or clothing that were popular in decades past and are currently making a comeback or were so unique that they defined the decade and are considered throwbacks.

Retro style would then imbue something that was fashionable, went out of fashion for decades, and then came back into fashion such as horn rim glasses, tight pants, earth tones, or neon colors. That doesn't mean that everything should come back but if someone was wearing something that screamed a certain decade identity and it wasn't original clothing from the era it would be retro chic modern clothing. I think the key element would be that decades have passed. It would be very hard to say a sweater or shirt you had that is still in your closet that has been there for ten years is iconic of the decade or retro. The reason would be even though it is getting old it is still probably commonplace in people's recent memory and they may even still have some of the same or people may be still wearing them and be out of current fashion. Given time however those overalls that you ditched in the 90s are coming back into style 20 years later.

People sometimes feel slighted that people don't validate their childhood memories the same as others especially our younger members who visit this site. Memories are precious to the memory holder and precious memories are being made all the time, every day. However they don't apply to nostalgia because there hasn't been enough passage of time and goods, or places may still be in existence and are readily available so the memories made with such could easily be replicated well at least the objects could be found easier than something or somewhere that is twenty years old at least and may not be around anymore. For current interests there are plenty of fan pages talking about and loving everything you grew up with even if it was less that a decade ago. Those things will become retro with time. But cannot meet the definition of something that evokes nostalgia because even though they are associated with happy memories they are missing the key element of the passage of time or enough time to be considered something of the past.

The opposite of retro would be current. So if there are plenty of things currently around then it may not be old enough to be retro yet. Current can be prevalent or popular, present, known. Until it becomes scarce, past, unpopular or enjoying a renewed popularity after falling from popularity, hard to find, and relatively unknown or unremembered it will be hard to call it retro or evoke the nostalgic feeling of, "Oh yeah I had totally forgotten about that but I remember now seeing it. Man I loved that back then."

NLogan wrote :

The term retro as it applies to style and fashion refers to using furniture, accessories, or clothing that were popular in decades past and are currently making a comeback or were so unique that they defined the decade and are considered throwbacks.

Retro style would then imbue something that was fashionable, went out of fashion for decades, and then came back into fashion such as horn rim glasses, tight pants, earth tones, or neon colors. That doesn't mean that everything should come back but if someone was wearing something that screamed a certain decade identity and it wasn't original clothing from the era it would be retro chic modern clothing. I think the key element would be that decades have passed. It would be very hard to say a sweater or shirt you had that is still in your closet that has been there for ten years is iconic of the decade or retro. The reason would be even though it is getting old it is still probably commonplace in people's recent memory and they may even still have some of the same or people may be still wearing them and be out of current fashion. Given time however those overalls that you ditched in the 90s are coming back into style 20 years later.

People sometimes feel slighted that people don't validate their childhood memories the same as others especially our younger members who visit this site. Memories are precious to the memory holder and precious memories are being made all the time, every day. However they don't apply to nostalgia because there hasn't been enough passage of time and goods, or places may still be in existence and are readily available so the memories made with such could easily be replicated well at least the objects could be found easier than something or somewhere that is twenty years old at least and may not be around anymore. For current interests there are plenty of fan pages talking about and loving everything you grew up with even if it was less that a decade ago. Those things will become retro with time. But cannot meet the definition of something that evokes nostalgia because even though they are associated with happy memories they are missing the key element of the passage of time or enough time to be considered something of the past.

The opposite of retro would be current. So if there are plenty of things currently around then it may not be old enough to be retro yet. Current can be prevalent or popular, present, known. Until it becomes scarce, past, unpopular or enjoying a renewed popularity after falling from popularity, hard to find, and relatively unknown or unremembered it will be hard to call it retro or evoke the nostalgic feeling of, "Oh yeah I had totally forgotten about that but I remember now seeing it. Man I loved that back then."
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Well said brother. I think what I find difficult is determining anything that might actually fit with your description as it pertains to anything beyond 1999. What from the 2000s will anybody look back on and say "Oh yeah! I had totally forgotten about that!" or see some kind of revival? I think those years still lack anything specific that defined them. Or at least defined them in a meaningful way to our culture as a whole.

Love the quality of the discussion here. 

The same debate is had over classic cars and films. When is a car a classic? They are nearly always age defined as well as iconic of a decade. For film age is also a factor as well as originality and if it is iconic. Because films portray set times within their stories a movie about the 50s or 60s made in the 80s like Stand by Me or 90s The Sandlot are not iconic of the 50s or 60s decades but are well remembered period pieces that are classic based on merit as 80s or 90s films. Some modern films are so good or iconic they are destined to become classics. All that is needed is the passage of time. For our purposes retro and classic are interchangeable. If you could not call something a classic defined by time then it is not retro. If it is a new classic it could be modern retro chic done in a classic style or destined to become classic but not yet. An example would be fidgit spinners. A useless yet prolific toy that has become insanely popular overnight that will become representative of this generation like the rubik's cube or slinky. It is not retro until you can say, "back in the day we had..."

Another indicator of retro is relevance. Is it still relevant today? Or has it been replaced? Look at mobile phones. Brick phones are retro, extending antennae are retro, flip phones are close but not yet plenty of people still have that dinosaur in their pocket, smart phones won't become retro for some time as they are still relevant. Even though the technology is advancing quickly enough to render past year's models obsolete they will not be retro until we are using completely new technology like hologram bracelets or something. Think film or music vinyl, 8 track, cassette, CD, streaming are a progression or reels, 8mm, 13mm, VHS, beta, laserdisc, DVD, blue ray, hd , 4d or whatever. Vinyl records are making a comeback as new retro and the classic vinyl ,8 tracks, or cassettes are definitely retro. Cds on the other hand even though they achieved widespread popularity in the 90s (a retro decade) are not because they are still relevant.