This chapter focuses on actuator technologies for pin-array tactile displays, crucial for presenting braille characters and tactile graphics to enhance accessibility for visually impaired users. While everyday haptic interactions (like phone vibrations) are common, the chapter details the evolution of pin-array displays from early, slow, and expensive electromagnetic or piezoelectric prototypes to modern commercial devices. It explores the human haptic sense (kinesthetic and tactile) and surveys diverse haptic display types, including vibrotactile (e.g., wearable arrays), force-feedback (e.g., PHANTOM device), shape-changing (e.g., FEELEX, Relief), electrotactile, and electrostatic displays, highlighting their respective capabilities and limitations for conveying non-visual information. Pin-arrays are identified as particularly promising for representing both text and graphics. The chapter details the history of braille displays and modern pin-array technologies, comparing key commercial systems and their features. However, significant challenges persist: hardware limitations (resolution, dot size/spacing, slow refresh rates, ergonomics), software gaps (lack of frameworks and standardized screen reader interfaces), user experience hurdles (interpretation complexity, tactile fatigue), high production costs affecting affordability, and durability/maintenance concerns. Overcoming these multifaceted challenges is essential for wider adoption and effectiveness of pin-array displays as assistive tools.