Differentiate between Show Grid and show thumbnail Option
Answers
Frameworks
Frameworks like Bootstrap or Foundation mostly base on using some helper structure of HTML based on rows and columns, styled with special CSS classes provided by framework. You use different classes to make result you need, like choosing a spacing between columns, number of columns, whether they span across all screen width, responsivness etc. Plese note, that those frameworks in newer versions may introduce some support for more CSS native grids / layouting methods described below.
Frameworks of course provide also a lot of other things, like a basic styling of the most common used elements.
CSS grids, flexbox, layouts
From some time we have a support for more modern layouting techniques in CSS. Depending on browser and version it may vary, as it was some time ago with border-radius or box-shadow.
Those new layouting methods allow to write less boilerplate HTML code to achieve the same effect. We also can use less CSS hack e.g. to center element vertically or achieve some more custom layout effect. More power is available on the CSS side, where we can control how a group of elements have to be rendered in the context of each other and container element.
BE SMART.......^_^