Human: What are the differences between a 401(k) and an IRA? Assistant: 
The main difference between a 401(k) and an IRA is that a 401(k) is sponsored by an employer, while an IRA is an individual retirement account. A 401(k) typically has more restrictions on withdrawals than an IRA, such as being subject to income taxes and penalties if you withdraw before a certain age or number of years. An IRA also allows for more flexibility in terms of investments, since it's not tied to any particular company.