Choosing the right electrode for welding
There are many factors that you should consider before you choose the right electrode for welding. First you should consider the type of metals that are being used. You cannot universally use the same electrode for every metal you weld together.
What you use for aluminum and brass will not be the same as you use for steel. Next is the resistance to corrosion by the electrodes. This is an important property for the storage of electrodes. If you are buying electrodes in a bulk for the use of a long term project, you should defiantly keep this factor in mind. Next is the type of coatings that these electrodes would carry.
Electrodes may be consumable or non consumable. A consumable electrode may melt during the welding process and add to the strength of the weld. Therefore it would depend on the type of welding process you are using to join two metals.