Knit and woven describe two different ways of constructing fabric. Neither is inherently better: the right choice depends on the garment, the yarn and the characteristics you want.
How the structures differ
A knitted fabric is made from interconnected loops of yarn. A woven fabric is made by interlacing two sets of yarns. A T-shirt is commonly knitted, while a classic poplin shirt is commonly woven, although clothing design offers many exceptions. The V&A’s survey of sweaters provides historical examples of knitted clothing and the variety of techniques used.
What you may notice
Some knitted fabrics stretch easily because of their looped structure, while many woven fabrics feel more stable. This is a general observation, not a rule for every item: fibre blends, elastane, yarn and weave or knit construction change the result. Woven stretch fabrics exist, and some knits have relatively little give.
Choose for the job
For a relaxed T-shirt, you may enjoy a soft knit. For a crisp shirt or structured jacket, a woven fabric may be a good starting point. Handle the material, check how it moves and review the care label. The best comparison is between actual garments, not category names alone.