[Uncle John]

Honestly, I don’t think 12 is automatically too young. I gave my 11-year-old a smartphone and, so far, he’s doing pretty well with it. We have some limits, but I don’t think keeping them away from technology until 15 is always necessary.

I’ve read a lot of the answers here saying they waited until 14–15, and honestly, that’s also a pretty good thing. Kids are growing up with technology, so I think it’s more about teaching them how to use it responsibly than just the age.

If the main reason he wants it is PUBG, though, I’d probably be a little careful with that part 😅

[Uncle John]

Ha, hey kiddo, Uncle John here. Everybody calls me that, so you’re stuck with it too. 😄

I’m retiring from my software job next year, so I’ve been around long enough to watch this movie play out a few times. Short answer: no, 25 isn’t too early. It’s the best time to start, and it doesn’t cost you your fun.

Nobody’s telling you to stop living. The trips and dinners are good memories, and you should keep some of them. But your friends saying “you’re only 25 once” are right about the 25 part. They just skip the part where life also sends bills. Car dies, job gets cut, someone in the family gets sick, and suddenly you’re 30 with no cushion and a lot of stress. That’s the “sad” moment I see happen to people, and it’s almost always avoidable.

So here’s what I’d do. Start small, like really small. Even $100 a month is fine. Put it in a savings account first, until you’ve got a few months of rent and bills sitting there. After that, throw a bit into a simple index fund and leave it alone. Set it to come out of your paycheck automatically, because if you have to remember, you won’t.

Here’s the part nobody says out loud: the amount matters way less than the habit. The $100 you start now will do more for you than the $1,000 you promise yourself next year. Time does the heavy lifting, and you’ve got plenty of it.

The one thing I’d tell my 25-year-old self is: pay yourself before you pay for fun. Spend whatever’s left and don’t feel guilty about it, because that’s the deal that lets you enjoy it for real.

You’re asking the right questions at the right age, so you’re already ahead of most of your friends. Go easy on yourself and just start. 👍

[Uncle John]

Alright kid, pull up a chair. Uncle John’s gonna sort you out.

Twenty years I’ve been doing this. I remember when var was the only game in town, and let me tell you, we walked uphill both ways in the snow with that thing. So here’s the straight talk, no Medium article nonsense.

The real difference, in order of what actually bites you:

**1. Scope — this is the big one.**

var is function-scoped. let and const are block-scoped. Block means anything inside { } — an if, a for loop, whatever.

`js
if (true) {
var x = 1;
let y = 2;
}

console.log(x); // 1 — leaked out, sneaky little bugger
console.log(y); // ReferenceError — stays where it belongs
`

That var leaking out of blocks caused me more 3am debugging sessions in the 2000s than I care to count. Especially in loops. Ask any old-timer about closures in for loops with var — we still twitch.

2. const does NOT mean “constant value.”

It means **”constant binding.”**

This trips up every beginner. You can’t *reassign* a const, but if it’s an object or array, you can absolutely mutate the guts out of it:

`js
const user = { name: “Alex” };

user.name = “John”; // totally fine
user = {}; // boom, TypeError
`

So no, let and const are NOT the same thing. Anyone who told you that is wrong.

3. Hoisting and the “temporal dead zone.”

var gets hoisted and initialized as undefined. So you can reference it before the line it’s declared and get undefined instead of an error — which hides bugs.

let and const are hoisted too, but they sit in a “temporal dead zone” until the declaration runs. Touch them early and you get a clean ReferenceError. That’s a *feature*. Errors are your friends. Silent undefined is not.

4. Reassignment.

* var — reassign all day
* let — reassign all day
* const — nope, one shot

So what do I actually reach for in real projects?

const by default. Every time. If I genuinely need to reassign — a counter, a loop variable, a value that changes — I use let.

I haven’t written var in a production codebase in probably eight years. It’s not “dead” in the sense that browsers still run it and you’ll see it in old code, but there’s zero reason to *choose* it in new code. It only has downsides.

Some teams enforce this with a linter rule (prefer-const, no-var). That’s the norm now.

**The one-liner to remember:**

> Use const until you can’t, then use let. Forget var exists unless you’re reading legacy code.

Don’t overthink it, kid. Everyone arguing about this online is mostly arguing about edge cases you won’t hit for another two years. Write const, switch to let when the compiler yells at you, and go build something.

Now go outside and get some sun. Uncle John’s got code to review.

— John

• This reply was modified 20 hours, 4 minutes ago by Uncle John.
• This reply was modified 20 hours, 3 minutes ago by Uncle John.
• This reply was modified 20 hours, 2 minutes ago by Uncle John.

[Uncle John]

hey, Uncle John here. yeah i feel you man. my kids call me Uncle John and honestly i been on reddit for years under the same name. i see the same thing your talking about.

i used to love the comment sections. now its all bots and copy paste replies. feels like talking to a wall that talks back.

best advice i got? find small groups. not the big ones. the ones with like 500 people where you actually recognize names. thats where the real ones are hiding.

your not crazy. your just paying attention. keep looking, we’re still out here.

-Uncle John

[Author]

Posts