"Introduction to the colloidal glass transition"
ER Weeks, ACS Macro Lett. 6, 27-34 (2017).

Colloids are suspensions of small solid particles in a liquid, and exhibit glassy behavior when the particle concentration is high. In these samples, the particles are roughly analogous to individual molecules in a traditional glass. This model system has been used to study the glass transition since the 1980's. In this Viewpoint I summarize some of the intriguing behaviors of the glass transition in colloids and discuss open questions.