Fixed
- Sizes of individual columns are fixed in width.
- Absolute positioning or float can be used to achieve the effect.
- Designer has more control over layout
- Avoids having very wide text areas
Fluid
- Sometimes called liquid or dynamic.
- Could be achieved by specifying all sizes in percentages.
- But can hit a number of bugs in early browsers like IE6
Elastic
- Define everything in units like ems
- Layout expands and contracts depending on font size
- With zoom features on some browsers, less relevant than it was in the past
Combination
- Probably the most frequently used
- One or two fixed width columns
- One column taking the remainder of the space
- Fixed design in terms of overall width but centred in the space available
