An asset is any item that has a value, some of which will be recorded on the balance sheet. Assets could be tangible or intangible. They are recorded on the balance sheet as assets with a positive value and liabilities with a negative value.
A balance sheet consists of assets, liabilities, and net worth. Your assets include everything you own that has monetary value.
Your liabilities are your debts—amounts you owe to others. Your net worth is the amount left when what is owed is subtracted from the value of what is owned—that is, if all the assets were sold at the listed value and all debts were paid in full.