The usage of symbols and special characters on Excel are about its purpose. These symbols and special characters are extremely useful for different things. I will show you where you can get the symbols, and special characters that you can use.
Insert a symbol
Click on Insert tab.
Click on Symbol.
Note: If the symbol is showing in gray, just click on the cell you want to insert the symbol or special character in, and it would stop showing gray.
Choose the Symbol
Choose Symbols or Special Characters (1), and then click on desired symbol or special characters (2), and then click Insert.