Difference Between $this and self in PHP

What is the real difference between $this and self:: ?

A simple Google search will return several sites that show a definition such as this one:
“Use $this to refer to the current object. Use self to refer to the current class.”

But unless you are a PHP pro, you will need an example to illustrate this definition:

Here is an example to help you out:

class ycsoftware
{
static $stat = "static property";

public $pub='non static property';

public function test_this_self ()
{
print 'Trying to call the static member with this' . $this->stat;
// Nothing will be printed

print 'Trying to call the non static member with this' . $this->pub;
// OK 'non static property' will be printed

print 'Trying to call the static member with self' . self::stat;
// OK

print 'Trying to call the non static member with self' . self::pub
// ERROR

}
}

Use $this for non-static members

Use self:: for static members only

Reference
http://www.phpbuilder.com/board/showthread.php?t=10354489

What is a Dual band Router?

What is Dual Band Router?

There are four protocols and two frequencies when dealing with WiFi. What are they?

Protocols A, B G and N and Frequencies 2.4 GHz and 5 GHz.

Some routers can only emit the 2.4 GHz frequency while others can only emit the 5 GHz frequency.

The Dual Band Router can emit both frequencies

Now what does that do for you?

1.  You router is compatible with a larger range of devices (a,b,g,n)
2.  The 5 GHz is supposedly faster than the 2.4 GHz when operating at the 5 GHz frequency
3.  The 5 GHz is supposedly more stable (less interferences)

Personally I have yet to see a household networking device that uses the 5 GHz exclusively.

To go further some devices are even locked into using the 2.4 GHz band.

So to Take advantage of the 5 GHz band, your device must support it.

If you want to transfer large files wirelessly and you have the extra cash the dual band is the way to go otherwise it may not be necessary yet (at least at the time of writing).

Reference
http://www.tested.com/news/wi-fi-80211n-24-ghz-vs-5-ghz-whats-the-difference/395/
http://arstechnica.com/gadgets/guides/2011/06/ask-ars-why-do-wireless-routers-still-cost-so-much.ars