A “rhythmic motif” is a short and often repetitive rhythm figure onto which any chords or melody notes may be grafted. Rhythmic motifs provide the building blocks for all musical ideas regardless of what instrument or musical style you play.
The one-bar motifs in Fig. 1, which consist of whole-, half-, quarter- and eighth-note groupings, are ideal for both repetitive strumming patterns and single-note lines. Grab a few chords, and, using either a straight- or swing-eighth feel, repeat each motif at least four times to establish a groove. Now try doing the same thing with any single-note riff that fits the motif - from growly, low-register licks to upper-register lead lines - incorporating string bends, hammer-ons, pull-offs and slides as you see fit. In both cases, you can form two-bar patterns by combining any two motifs. You can also replace any note with its equivalent rest.
Fig. 2 introduces dotted notes, ties and syncopations, or emphasized upbeats. Again, each motif can be played using straight or swing eighth-notes. Put them through the same drill and work with each motif until it becomes a natural part of your vocabulary. (Tip: Try clapping, tapping, or playing each rhythm on muted strings before assigning chords or single notes to it.)
All of these motifs can be converted to double-time simply by halving the value of each note - whole-notes become half-notes, half-notes become quarter-notes, quarter-notes become eighth-notes and eighth-notes become sixteenth-notes. This turns a two-bar motif into a one-bar motif, cuts a one-bar motif down to a half-bar, and so on.
Conversely, any rhythm can be half-timed by doubling the duration of each note. In half-time, a one-bar motif expands to two bars, a two-bar motif becomes four bars, etc. Read the chart in Fig. 3 from left to right for double-time conversion and right to left for half-time.
All of the previous motifs occur in every musical style, and internalizing how they look and sound will help you to recognize them. Rhythmic motifs are everywhere, so get to know them!