Chris today

float f = 5.6789;
char s[11];

void setup()
{
    Serial.begin(115200);
    delay(1000);
    dtostrf(f, 8, 2, s);
    Serial.println("|" + (String)s + "|");

}



Integer to formatted string itoa()
int i = 2147483647;  max int on avr processor
char s[11];

void setup()
{
    Serial.begin(115200);
    delay(1000);
    itoa(i, s,10);
    Serial.println("|" + (String)s + "|");

}

Serial.println multiple vars and strings

Serial.println("|" + (String)s + "|"); where s is a variable