//Easier but rarely used or mostly used by experienced scripters
new 
    i = 0;

while(i < MAX_PLAYERS)
{
    //do stuff here
    i++;
}

// Mostly used by beginners, the code looks long, but it's mostly used by people
for(new i = 0; i < MAX_PLAYERS; i++)
{
    // Do stuff here
}

//loops means increasing the variable by 1 until it reaches the maximum value.

new 
    i = -1;

// increasing i by 1 and it returns the new value - it basically starts as: while(0 < MAX_PLAYERS) and it is increased later on..
while (++i < MAX_PLAYERS) 
{
    //do stuff here
}