Golang Tour Excercise Square Root

I'm trying to figure out why 1e-10 is used in this code. I was running through the exercises and got stuck on Next, change the loop condition to stop once the value has stopped changing (or only changes by a very small delta). See if that's more or fewer iterations. After not figuring it out, I searched and found this solution by someone else.

In a lot of solutions, I saw 1e-10 as part of an if statement within the for loop. In Golang, does it mean that 1e is risen to the (-10) power? Is it like, automatic for Golang? So basically normally I'd assume it would be written as 1e^(-10)?

package main

import (
    "fmt"
    "math"
)

func Sqrt(x float64) float64 {
    z := float64(2.)
    s := float64(0)
    for i := 0; i < 10; i++ {
        z = z - (z*z - x) / (2 * z)
        if math.Abs(z-s) < 1e-10 {
            break
        }
        s = z
    }
    return z
}

func main() {
    fmt.Println(Sqrt(2))
    fmt.Println(math.Sqrt(2))
}

Thanks for any/all help one may provide!

1e-10 is a floating-point literal with the value 1 to the power minus 10.

> The Go Programming Language Specification
>
> Floating-point literals
>
> A floating-point literal is a decimal representation of a
> floating-point constant. It has an integer part, a decimal point, a
> fractional part, and an exponent part. The integer and fractional part
> comprise decimal digits; the exponent part is an e or E followed by an
> optionally signed decimal exponent. One of the integer part or the
> fractional part may be elided; one of the decimal point or the
> exponent may be elided.
>
> float_lit = decimals "." [ decimals ] [ exponent ] |
> decimals exponent |
> "." decimals [ exponent ] .
> decimals = decimal_digit { decimal_digit } .
> exponent = ( "e" | "E" ) [ "+" | "-" ] decimals .
>
> 0.
> 72.40
> 072.40 // == 72.40
> 2.71828
> 1.e+0
> 6.67428e-11
> 1E6
> .25
> .12345E+5

The same, I was on the exercise again, trying to recollect, how I solved the task in a previous time, and these words:

> Blockquote
change the loop condition to stop once the value has stopped changing

hinted that it is better to change the loop conditions than to add additional "if" condition...

it is very likely that knowing how Newton's method actually works will only allow changing the conditions of the cycle itself.

i<int(x)

the hint:

https://gist.github.com/smirnoffs/6afc2dc31988c4935b139a6d0fea81a9

p.s

IMO, it will allow the code look more elegant.