Check out example codes for "font weight". It will help you in understanding the concepts better.

Code Example 1

p {  
  font-weight: normal;
} 
a {  
  font-weight: bold;
}  
p.thick {  
  font-weight: 780;
}

Code Example 2

font-weight: bold;

Code Example 3

/* Valeurs avec un mot-clé */
font-weight: normal;
font-weight: bold;

/* Valeurs relatives à l'élément parent */
font-weight: lighter;
font-weight: bolder;

/* Valeurs numériques */
font-weight: 1;
font-weight: 100;
font-weight: 100.6;
font-weight: 123;
font-weight: 200;
font-weight: 300;
font-weight: 321;
font-weight: 400;
font-weight: 500;
font-weight: 600;
font-weight: 700;
font-weight: 800;
font-weight: 900;
font-weight: 1000;

/* Valeurs globales */
font-weight: inherit;
font-weight: initial;
font-weight: unset;

Code Example 4

font-weight: 200; /*100 200 300 400 500 600 700 800 900 
					Defines from thin to thick characters. 
					400 is the same as normal, 
					and 700 is the same as bold*/

Code Example 5

font-weight: normal|bold|bolder|lighter|number|initial|inherit;

Code Example 6

p.normal {
  font-weight: normal;
}


p.thick {
  font-weight: bold;
}


 p.thicker {
  font-weight: 900;
}

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