Ties can be used to connect quarter notes and eighth notes, as in the examples here. This creates an "off-the-beat" feel, which is known as syncopation. When a chord change is anticipated by half a beat, through using ties across the bar lines, it is described as giving the rhythm a push.
This example uses both rests on the beat and ties on the beat to create syncopation. Notice the use once again of the first finger across the 3rd and 4th strings at the 2nd fret.
This symbol is called common time. It means exactly the same as *. The next example uses the common time signature.