Trade Lines are a part of the TransUnion Full Credit report:
Here is a sample Trade Lines snapshot with RentPrep's TransUnion Full Credit report:
Account Types:
O - Open Account : "Open account occurs when a seller ships the goods and all the necessary shipping and commercial documents directly to a buyer who agrees to pay a seller’s invoice at a future date."
Source - Wikipedia
R - Revolving or Option : "A revolving account is an account created by a lender to represent debts where the outstanding balance does not have to be paid in full every month by the borrower to the lender." Source - Wikipedia ... Credit cards are a common example of a revolving account.
I - Installment : "Installment accounts are those that have a fixed payment for a fixed period of time. As with revolving accounts, you are not required to pay them in full each month. You are allowed to make a payment that is going to be the same every month until the loan is paid in full."
Source - Credit.com
M - Mortgage : "Used to raise funds to buy real estate; or alternatively by existing property owners to raise funds for any purpose, while putting a lien on the property being mortgaged. The loan is secured on the borrower's property."
Source - Wikipedia
C - Check credit (line of credit) - "A line of credit, abbreviated as LOC, is an arrangement between a financial institution, usually a bank, and a customer that establishes a maximum loan balance that the lender permits the borrower to access or maintain."
Source - Investopedia
Responsibility
This is the subject who the background check was run on and their relationship to the account being examined.
A - Authorized user of shared account : "Authorized users piggyback on the credit of a friend or relative. These users are entitled to use the credit extended to the cardholder, but have no legal responsibility to pay the bill."
Source - Bankrate.com
C - Joint contractual liability : "Joint account holders actually share ownership of the account and both are liable for repaying the debt. A joint account must be opened by the account holders at the same time. "It's literally like a joint liability account," Gupta says. "The advantage is that both credit histories get updated, and both account holders are legally responsible for the debt."
Source - Bankrate.com
I - Individual account for sole use of customer : An account where the subject is the sole owner and no one else is liable or connected to that account.
M - Account for which subject is liable but co-signer has liability if the maker defaults : If the subject buys a vehicle but needs a co-signer on the account you would see this "M" code
P - Participant in shared account which cannot be distinguished as C or A : In these situations the borrower is joint on the account but the contractual liability can not be determined.
Source - advcredit.com
S - Account for which subject is co-signer and becomes liable if maker defaults : In this case, the subject may have a friend or relative that purchased a vehicle and co-signed for the loan.
T - Relationship with account terminated : In this case the subject is no longer associated with the account
U - Undesignated : The account hasn't been designated yet, perhaps it's a recently opened account
X - Deceased : The subject has been reported as deceased