Schematic cartoon of inner disk-star connection. The star (black quarter circle on the left) has a radius of R_⋆ and rotates with Ω_⋆. Disk material (gray area) flows from the outer disk toward the inner disk radius r_in, where it is forced into funnel flows and is accreted onto the star (e.g., Romanova et al. 2004; Bessolaz et al. 2008; Steiner et al. 2021) with an accretion rate of Ṁ_W. The accreted disk material increases the stellar angular momentum by Γ_acc. Based on the model, a specific fraction of the accreted mass is driven into a stellar wind, which removes mass and angular momentum from the star (Ṁ_ref and Γ_W, respectively). The Alfvén radius r_A acts as a lever arm for this stellar outflow. We note that this cartoon is not to scale and we can usually assume r_A ≫ R_⋆. Angular momentum can be transferred toward or away from the star (Γ_ME), depending on the position of r_in with respect to the corotation radius r_cor (e.g., Zanni & Ferreira 2013). Finally, magneto-centrifugally driven disk winds remove angular momentum and mass from the disk before it can be accreted on the star (e.g., Königl et al. 2011; Bai & Stone 2013). We note that disk winds are not included in our model.