Field tile makes up the bulk of most tile installations on floors, walls and backsplashes. It's also frequently used as a frame for mosaics, where border tiles might distract from the design.
Field tiles are usually mass-produced. Handmade field tiles are more expensive, but their slight color variations can produce a richer look.
Most field tiles are square, but rectangles are also common. Triangular field tiles can add visual interest. Hexagonal tile is a popular choice for vintage-look bathrooms.
Square field tiles are available in sizes from one to about eight inches across, and other shapes come in equivalent size scales. Sizes are often slightly smaller than stated to allow for grout lines.
You can get loose field tiles, but smaller sizes usually come attached to a mesh backing for easier installation.