concatenation operator
The & (ampersand) character is used to concatenate, or join, two or more values or the contents of two or more cell references. Here are some examples:
="Abc"&"Def" returns "AbcDef".
="Abc"&A1 returns "Abc2" if cell A1 contains 2.
=A1&A2 returns "12" if cell A1 contains 1 and cell A2 contains 2.
=B2&", "&E2 returns "Last, First" if B2 contains "Last" and E2 contains "First".
=60&60 returns ""6060".