For questions on the envelope system of budgeting, or its modern digital equivalents.
Traditionally, the envelope system is a method of budgeting where a person places cash into various envelopes set aside for various purposes (a grocery envelope, a transportation envelope, an entertainment envelope, etc.) Cash is taken out as it is spent, and when the envelope is empty, you are done spending in that category until you put more cash into the envelope.
Some modern budgeting software packages provide a digital version of the envelope system, where the user funds digital envelopes with money and the software deducts the envelope balances as the user makes purchases.