The US Internal Revenue Service (IRS) released Publication 17 (Tax Guide 2018 for Individuals). The publication is dated 30 January 2019 and is intended for use in preparing tax returns for 2018.
Publication 17 describes the general rules for filing a US federal individual income tax return. It supplements the information contained in the Instructions for IRS Form 1040 (US Individual Income Tax Return).
Publication 17 includes a summary of important tax changes that took effect in 2018 pursuant to the Tax Cuts and Jobs Act (TCJA).