[DonRotolo]

You must be used to solder that has a flux core. Wasn't always that way.

Liquid (or paste) flux is just that, and you brush a little of it onto what you need to solder, then heat & apply solder. Radio Shack sells both I believe.

It comes in real handy when soldering large wires (you don't need to melt 8" of solder to get enough flux in there) or wires that are a little bit less than shiny-new (these don't take to solder very well; a little dab makes them wet out like fresh copper). Also handy when soldering PC Boards; solder doesn't bridge across traces/pads when there is enough flux. Super handy for surface mount ICs to get rid of solder bridges too.

Just be sure the flux is electronics (e.g., Rosin) type and NOT "acid" flux (which is only good for plumbing, it'll destroy your electronics very quickly).