Many public companies offer employee stock purchase plans or ESPPs to all of their employees. They are much more common than stock options or restricted stock.

These plans let employees have money withheld from their paychecks to buy company stock periodically. During an offering period, usually six or 12 months, money builds up in an interest-bearing account. At the end of this period, the money is used to buy shares, often at a discount of up to 15 percent from the market price. Many plans use the market price either on the first day or the last day of the period, whichever is lower. This makes ESPPs a very low-risk proposition.