Soldering makes quick and neat connections to electronic equipment, plumbing and jewelry. Heating the metals with a soldering iron or torch melts the solder onto the joint, forming the bond as the solder cools.
Soldering requires temperatures around 400°F. Welding requires far higher heat.
Since solder flows at lower temperatures, the metals connected do not melt or warp. They maintain their original size and shape, even if the person soldering makes mistakes.
The solder flows between the electrical connectors to bond them together. Since the solder is metal, it conducts electricity.
Circuit boards floated on a molten solder bath make multiple connections with a single operation. The solder only sticks to the components and not the board itself.
Soldering does not require any particular skill. You can learn to solder electronic components, plumbing and jewelry with easy-to-follow instructions found on several websites.