Table 1.

Characterization of directional textured surfaces.

Category	Figure examples
Structure
hair/rod/groove	2a,b,d,g; 3a–k; 4a–c,e–g
scales	2e
surface contour	2c,f; 3l; 4h
multi-scale	2a,b,d,e; 3k
Directional property
dry adhesion	2b; 3i–k
lubricated adhesion	2a; 4d
wet adhesion	2c–f; 3a–h; 4a–c,e–f
mechanical force	2g; 4g
flow streamlines	3l
Usage
water repellency	2d,e; 3a–c,e,f; 4b,c
water spreading	3d,g,h; 4a
transport	2c–f; 3a–c,e,f,l; 4b–e,g,h
adhesion	2a,b,g
Fabrication (engineered surfaces)
template-free	3e,f; 4b,c,e–g
template-assisted	3j–l
lithographically patterned	3a–d,g–i; 4a,h