Leaves stalked: in this case the blade is clearly restricted at base and attached to the stem by an evident stalk, such as in Atriplex...:

...in Chenopodium..:

...and in several species of Plantago:

Leaves not stalked: the leaves are sessile (with no evident stalk) and in some cases (such as in the families Poaceae and Cyperaceae) the blade is prolonged into a sheath surrounding the stem: