What is the difference between ++a and a++ in javascript loop?

[College Student]

Bit confused as to what ++a and a++ mean, I assume they do not mean the same thing? I know one adds one to your value but what does other do etc, any good websites that explain basic java script

[JeckJeck]

++a is add 1 THEN take the vaue
a++ is take the value THEN add 1
for example

a = 0
if (a++) // this will be false
{
// here a will equal 1
}
a = 0
if (++a) // this will be true
{
// here a will equal 1
}
Practical uses
for (a = 0;a++ < 10; a++)
{
// do something exactly 10 times
}
for (a = 0; ++a < 10; a++)
{
// do something exactly 9 times
}