Dipoles and Center Fed Inverted Vee Antennas
One of the most basic and arguably simplest antennas is the half wave dipole. It pretty closely matches our 50 ohm feedlines. Is very forgiving as to materials used and is easy to fabricate. It is also easy to deploy if you have two trees or other things to tie the ends off to. Height is important but not critical. By that I mean it will work at almost any height. When hung higher it tends to work better for longer distances. Lower and it is more like a NVIS (Near Vertical Incidence) antenna meaning it works best for shorter distances. All that is subjective so generally you can just do the best you can and use it!
A very useful variation is the inverted vee. It is simply a dipole supported at the middle feed point with the legs stretched downward toward the ground, an upside down "V". You can find all kinds of ideas about how height of the center and angle of the legs impact its performance but in practice, as with the dipole, do the best you can and it will work. The leg lengths may have to be adjusted somewhat from the ideal dipole leg lengths but otherwise it is made just like a simple dipole.
The links on this page are to various versions of the dipole/inverted vee that I have played with.