HP 35s HP 35s scientific calculator - User Guide - Page 66

In ALG mode, you can store an expression into a variable; in this case, the value of the expression is stored in the variable rather than the expression itself. Example: Keys: Display: Description: Enter the expression, then proceed as in the previous example. Each pink letter is associated with a key and a unique variable. (The A..Z annunciator in the display confirms this.) Note that the variables, X, Y, Z and T are different storage locations from the X- register, Y-register, Z-register, and T-register in the stack. Storing and Recalling Numbers Numbers and vectors are stored into, and recalled from, lettered variables by means of the Store and Recall () commands. Numbers may be real or complex, decimal or fraction, base 10 or other as supported by the HP 35s. To store a copy of a displayed number (X-register) to a direct variable: Press  letter-key . To recall a copy of a number from a direct variable to the display: Press  letter-key . Example: Storing Numbers. Store Avogadro's number (approximately 6.0221 × 1023 ) in A. 3-2 Storing Data into Variables