Simplify the following text for a Grade 11 native English-speaking person.
Original: Soldering is a process in which two or more metal items are joined together by heating them with a soldering iron and then melting and flowing a filler metal into the joint , the filler metal having a relatively low melting point .
Simplified: Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal into the joint , the filler metal having a relatively low melting point .