Common variation of the blues

I - IV - I - I  <- here
IV - IV - I - I
V - IV - I - I

There are other variations, of course.

I need to correct you on this... the I chord is known as the TONIC chord.

I wish I understood this theory, I played guitar for well over 30 years. I don't suck at it by any means, though I don't know a thing about it.  I lost the passion a few years ago and have not picked it up since sadly.  I think I will plug my guitar in right now

If I find anything then I will come back and ask for some direction. Thanks!!!

More variation, and bluesier.

I - IV7 - I - I7
IV7 - IV7 - I - I
V7 - IV7 - I - I

To denote beats, use the / mark.  The vertical | is a bar line.  ||: and :|| are repeats, that is, you
repeat everything between these markings.  It would look a little better, be easier to read, if you
make the | (bar lines) a little taller than the ///.

||: I / / / | IV7 / / / | I / / / | I7 / / / |

IV7 / / / | IV7 / / / | I / / / | / / / / |

V7 / / Vb7* | IV7 / / / | I / / / | / / / / :||

* For example, if playing in C, you would play a barred G7, then on the 4th beat a Gb7, that is, just
slide down a half step, and then down another half step to the IV7.

So you could write it like this.  How about G, a good key for guitar.

||: G / / / | C7 / / / | G / / / | G7 / / / |

C7 / / / | C7 / / / | G / / / | / / / / |

D7 / / Db7 | C7 / / / | G / / / | / / / / :||

While the bass line will pick up the IV a higher instrument can drop a Im over the IV7 in the first
and second 4-bar phrases.  That will in effect be a IV9, and a good blues effect.

||: G / / / | C7(Gm) / / / | G / / / | G7 / / / |

C7(Gm) / / / | C7 / / / | G / / / | / / / / |

D7 / / Db7 | C7(Gm) / / / | G / / / | / / / / :||

Someone just shared this course in another forum. I signed up but haven't taken any of the course yet. Just thought I'd share.

Kinda bummed that after all these years I didn't click on this thread until this week. Some really good info in here.
As a young lad I had learned how to read, write, and play music...then summarily forgot all that 'formal' stuff in favor of 'teaching myself guitar' in my teens

After pursuing real lessons, then music school, then more lessons, I had accumulated (and remembered) enough theory to at least pass as a guitarist. Now...decades later I've found myself trying to complete my training....like Luke going back to Yoda

I put up a local ad trying to give lessons for beginners...trying to make some side cash. Got a student pretty quickly and as I was preparing lessons I realized both how much I actually did kinda know, yet at the same time, how much I didn't.

It was already said in a way in this thread...understanding the theory behind how chords are built and how certain tones resolve them really is the secret sauce behind playing....like learning a new language. As a young guitarist, as much as I wanted to solo, I couldn't ever seem to find notes that made any sense. Learning scales was like finding a key to a locked door...and I stayed with that for many years.

Now I find myself tackling more of the jazzy type progressions and chords...expanding the complexity and trying to take my playing up a notch.

I hope more folks will chime in with thoughts, lessons, and offerings.
What I'd love to see are thoughts on which modes to use over what chordal tones.
There are tons of instructions out there for how to learn and memorize the modes, but very little that is useful in terms of how they ought to be used. I play over tracks when I practice scales and have found little application for many of the modes....I assume because of the progressions and voicings I am playing. I use Ionian as my base, and have found some application for Dorian and Lydian. I have found almost no way to musically apply the Locrian mode to my music (which is mostly hard rock, edgy bluesy, and psychedelic rock). I kinda get the taste of the Phyrgian mode, but just kinda feel like the harmonic minor scale does that theme better....at least for the music I tend to play.

I tend to use Ionian and pentatonic for damn near everything....with some harmonic minor riffs thrown in at times.
Trying to find some other scales / modes that will introduce new flavors.
Any suggested chord progressions and pairings for scales would be very appreciated.

Whoa, boy did that catch my attention when I saw Hemi-Cuda appear as a thread author in active topics. I had no idea this existed. Tag!

Page 1 definitely has some names from the past...shame that some who contributed so much in this particular area got sidetracked in others.

I've been a composer for 40 years.  Piano is my main instrument, but I also own and program synthesizers.  Lots of fun.

But this opening statement by this guy is actually wrong.  Music is not a language.  Music is an art form consisting of sounds comprised of 4
elements:

1) Beat
2) Rhythm
3) Melody
4) Harmony

A language means that people can communicate with one another and understand what is said.  If I play an 8-bar chord progression, or a 12-bar melody, could anybody say they knew what was said?  It would be utter foolishness to speak as such.

The term "Music is a language" is something people throw around all the time without really understanding the words they are saying, and the meaning of those words.  We all know what is implied, but technically music is not a language.  It does not have verbs and nouns, adjectives and adverbs, etc.

Don't get too caught up in notation unless of course you want to.  It's not essential to learning theory though, they're two different things.
Notation might help illustrate some concepts on paper better, maybe, but it definitely is not a must.  To the average musician who wants to play rock, blues, folk, or pop, and do some writing, basic theory is important;  reading is not.
If you get into mainstream jazz or classical, then you better know your squiggles, but otherwise a well developed ear and an understanding of the relationship of notes and keys  is the key.  Uh, no pun intended.

Cool thread, I've picked around on guitars for 25 years but I've decided to learn more about music theory.  I was in band for many years and music isn't foreign to me but it's also been a while too, so in a way it's like starting all over again, well mostly.   Been watching some guys on YT and playing with triads which has got me wanting to go further.    Guitar is an enjoyable instrument for sure, challenging for sure at times but also rewarding.  It gives you plenty of stuff to learn so it really never gets boring, depending on your mindset.