just to add to previous posts, the "bind" function is telling your transmitter its your receiver, they "bind" together, otherwise they will not recognise each other. The process is simple, I have a spectrum DX6i, this is how that tx does it, yours might be slightly different, so read the instructions.
First, plug in the receiver power source, with transmitter turned off. If your power source does not have the right connector, you need to sort this out first, a visit to local model shop or maplins will help. Just cut the lip off the esc so it fits.
The receiver will probably be flashing, saying hey Ive got power, but no signal from a transmitter!
On the DX6i, you pull the trainer switch (top left) and whilst holding the switch turn on the tx, it will go into bind mode, a minute later, the receiver will stop flashing and its bound. This normally only occurs once, once done its never done again!
A lot of esc's have a built in bec (battery eliminating circuit) which does exactly that, eliminates the need for extra battery power for the receiver. High voltage circuits, etc, usually require extra seperate power. When flying aircraft, or helciopters, weight is the enemy so the last thing you want is to be dragging 4 aa batteries around.
I use spektrum gear for aircraft, helicopters and boats, they are excellent, with superb customer service from horizon hobby.
The dx6i is very popualr as it has 10 model memory, is digital, and has various other tricks very useful and easy to use specifically for aircraft and helis, not sure without googling what the dx5 has.