It’s a feature of the guitar that the neck forms a grid. There are lots of benefits to this that you’ll discover as you learn more – certain chord shapes and scales are moveable, meaning you only need to learn one pattern or shape, and you can move it around up and down the fretboard to play lots of scales. It would be impossible to do this on a piano keyboard, for example.
But that does mean that all the notes look the same, unlike a piano keyboard.
Here’s what you need to know about the way the fretboard works:
The lowest note on each string is the open string. As you press on each fret from 1 2 3 4 5 etc moving up towards the body of the guitar, the notes sound higher pitches.
In terms of the names of the notes, there are seven letters from A to G and these are used to name the notes. As you go each letter further into the alphabet, the notes are higher in pitch. So a B is higher in pitch than an A. Conversely, an E is lower in pitch than an F.
There are two frets in between every note except for B and C, which are adjacent, and E and F, which are adjacent. This is totally consistent, so anywhere on the guitar you find a C, B is right next to it (one fret towards the headstock) and anywhere you find an E, F is one fret closer to the body of the guitar.
So for the open A string, the notes are spaced like this: