When more than one lines are written in the code than the browser will not show line break in output of that code. See the below code.
Output of Code
To insert a line break that will be shown in the browser use <br> tag. There is no ending tag for <br> because we are not applying style on text to show in the browser like we did in headings.
Example of <br> tag in HTML
This is First Line. <br>
This is Second Line. <br>
This is Third Line. <br>
Q. Is it good practice to use <br> tags in code ?
Ans. No , but in starting you should use <br> tag in code. You can use <p> tags instead. After learning CSS you will not use <br> tag a lot.
Q. What should I do if I want to increase the space between two words in code ?
Ans. You can use   to insert an extra space in your HTML code.