HTML Entities

Reserved characters in HTML must be replaced with entities. For example, the less-than sign < is written as <, and the greater-than sign > is written as >.

Some characters are reserved in HTML. If you use the less-than (<) or greater-than (>) signs in your text, the browser might mistake them for tags.

You can show reserved characters using an entity name, written as &entity_name;, or an entity number, written as &#entity_number;. For example, a less-than sign can be written as < or <. Entity names are easier to remember than entity numbers.

A common entity is the non-breaking space,  . It is a space that will not break into a new line, so two words joined by it stay together, which is handy when a line break would be disruptive (for example in "10 km/h" or "10 PM").

It also prevents the browser from collapsing spaces. If you type 10 spaces, the browser keeps only one; to add real spaces, use  . There is also a non-breaking hyphen, ‑, which is a hyphen that will not break onto a new line.

Some common entities (character, name, number): non-breaking space ( ,  ), less than (<, <), greater than (>, >), ampersand (&, &), double quote (", "), single quote (', '), cent (¢, ¢), pound (£, £), yen (¥, ¥), euro (€, €), copyright (©, ©), registered trademark (®, ®), and trademark (™, ™).

Entity names are case sensitive.

A diacritical mark is a glyph added to a letter. Some marks, like the grave and acute accents, are called accents. You can combine a mark with a letter to make a character that is not in the page's character set.

For example, à produces à, á produces á, â produces â, and ã produces ã. The same marks work on other letters, so Ò produces Ò, and so on. There are more examples in the next chapter.