Standard effects are listed in the Effects panel and are organized into two main bins, Video Effects and Audio Effects. Within each bin, Premiere Pro lists effects by type in nested bins. For example, the Blur and Sharpen bin contains effects that defocus an image, such as Gaussian Blur and Directional Blur.
Find audio effects in bins named for the type of audio clips they support: mono, stereo, or 5.1.
You can also locate an effect by typing the effect name in the Contains box.
To open the Effects panel, choose Window > Effects, or click the Effects tab.
Karl Soule explains the meanings of the icons for 32-bit (32-bpc) and YUV effects in a pair of articles from his Adobe blog: