Widely used as a purple dye in textiles and paper industries for coloring. Employed in microbiology as a key component in Gram staining, helping to differentiate Gram-positive and Gram-negative bacteria. Acts as an antifungal and antiparasitic agent in aquaculture, particularly for treating fish eggs and controlling fungal infections. Used in some ink formulations for writing and printing. Also applied in histology as a staining agent for microscopic examination of tissues. Has been utilized in the past as a topical antiseptic, though this use is now limited due to toxicity concerns. Serves as an indicator in analytical chemistry due to its distinct color change under different pH conditions.