Begin a Wolfram Language session

Every Wolfram Language symbol exists in a “context”. Built-in symbols are in the System` context, and by default, user-defined symbols are in the Global` context. When a new session is started, the Global` context is normally empty:

Create a symbol

When you create a symbol, it is added to the Global` context:

Define a function

When you define a function, the function name is added to the Global` context along with the function’s parameters:

Find all user-defined symbols

All user-defined symbols (including functions) are in the Global` context:

Find all user-defined functions

In contrast to other symbols, function symbols have DownValues, the transformation rules that define the function. To get a list of just the names of function symbols you have defined, select the names of symbols that have DownValues:

Notes

Use Information (short form: ?) to get an interactive listing of user-defined symbols. Click a symbol to see its definition and usage message, if there is one: