The vector stencils library "Wireframe grid" contains 7 web page layout design patterns.
Use these grids to position content and widgets on your web pages using the ConceptDraw PRO diagramming and vector drawing software.
"In graphic design, a grid is a structure (usually two-dimensional) made up of a series of intersecting straight (vertical, horizontal, and angular) or curved guide lines used to structure content. The grid serves as an armature on which a designer can organize graphic elements (images, glyphs, paragraphs) in a rational, easy to absorb manner. A grid can be used to organize graphic elements in relation to a page, in relation to other graphic elements on the page, or relation to other parts of the same graphic element or shape. ...
While grid systems have seen significant use in print media, interest from web developers has only recently seen a resurgence. Website design frameworks producing HTML and CSS had existed for a while before newer frameworks popularised the use of grid-based layouts. Some grid systems specify fixed-width elements with pixels, and some are 'fluid', meaning that they call for page element sizing to be in relative units like percentages, rather than absolute units like pixels or points." [en.wikipedia.org/wiki/Grid_(graphic_design)]
The webpage layout patterns example "Design elements - Wireframe grid" is included in the Website Mockup solution from the Software Development area of ConceptDraw Solution Park.