35 ILCS 185/5-10
As used in this Act:
"Certified service provider" means an agent certified by the Department to perform the remote retailer's use and occupation tax functions, as outlined in the contract between the State and the certified service provider.
"Certified automated system" means an automated software system that is certified by the State as meeting all performance and tax calculation standards required by Department rules.
"Department" means the Department of Revenue.
"Remote retailer" means a retailer as defined in Section 1 of the Retailers' Occupation Tax Act that has an obligation to collect State and local retailers' occupation tax under subsection (b) of Section 2 of the Retailers' Occupation Tax Act.
"Retailers' occupation tax" means the tax levied under the Retailers' Occupation Tax Act and all applicable local retailers' occupation taxes collected by the Department in conjunction with the State retailers' occupation tax.
35 ILCS 185/5-10