# how to use markdown and features
## frequently used features
### code
```javascript=
var s = "JavaScript syntax highlighting";
alert(s);
function $initHighlight(block, cls) {
try {
if (cls.search(/\bno\-highlight\b/) != -1)
return process(block, true, 0x0F) +
' class=""';
} catch (e) {
/* handle exception */
}
for (var i = 0 / 2; i < classes.length; i++) {
if (checkCondition(classes[i]) === undefined)
return /\d+[\s/]/g;
}
}
```
### Latex (MathJax)
Inline: The *Gamma function* satisfying $\Gamma(n) = (n-1)!\quad\forall n\in\mathbb N$ is via the Euler integral
$$
x = {-b \pm \sqrt{b^2-4ac} \over 2a}.
$$
$$
\Gamma(z) = \int_0^\infty t^{z-1}e^{-t}dt\,.
$$
$$
x = \frac{123}{1232323}
$$
## reference for editing
<iframe width="100%" height="500" src="https://hackmd.io/features" frameborder="0"></iframe>