Does magnetism have a frequency?

DC is a constant flow and does not have a frequency.

RF has frequency.

AC has frequency.

magnetism has no frequency.

No more than an electric field has a frequency. AC currents are really electromagnetic waves propagating through a wire. The electric field as well as the magnetic field varies and this can be characterized with a frequency. This is because an electromagnetic wave is comprised of BOTH a varying magnetic field as well as a varying electric field.

A constant magnetic field does not have a frequency (because it's constant) so no the Earth's magnetic field does not have a frequency...although it does vary from place to place and it does change over time (slightly), so in some sense that's "like" a frequency...but generally speaking frequency describes a "well-behaved" wave, not randomness, which better describes the varying magnetic field of the Earth (again it only varies slightly over time).

Again, an rf signal is an electromagnetic wave which (to reiterate) is comprised of both a varying magnetic field and electric field...which I should say is closely related...that is you can figure out the magnetic field by knowing the electric field or vice versa. The electric and magnetic field in an EM wave are perpendicular to each other, both of which are perpendicular to the direction of motion (hence it is a transverse wave)

An oscillating magnetic field has a frequency. An unchanging magnetic field does not (more specifically, it has a frequency of zero). Frequency describes how rapidly a cyclic action occurs. No cyclic action means zero frequency.

The magnetic field is simply that portion of the electromagnetic force which is generated by the velocity of charge. Likewise, the electric field is that portion of the electromagnetic force which is generated by the position of charge.

But do keep in mind that a field is not a true entity. Rather, a field is a mathematical abstraction, a tool used by humans to understand the behavior of a physical system.

We talk about fields as if they were a bunch of arrows, permeating all of space. But in reality, that's just a convenient way to think about it. A particle does what it does. It does not 'look around' or 'sniff' the local field, then decide what to do. It simply moves around. We've discovered that the mathematical construct of a field is one way to explain why it does this.

"magnetism" has many common meanings

Physics since the 1800s has understood that all magnetism is a effect of electric charge in motion

It does not exist "on its own"

Frequency would relate to the number of times a second the electric charge changes

it could even be a constantly increasing charge or field and NOT be repeating ( almost impossible)

Absolutely constant Charge or field is also impossible but if the F is very very low, that is the T for change is very very long ( slow change, almost DC direct current, there would be no measurable Magnetic field

the study of Electro -magnetic theory takes at least a year or more to really understand

Magnetic field has intensity and direction and if it is changing some frequency, which need not be constant

the earths field varies over days and years and thousands of years. according to the magnetic alignment of old rocks

in short "Magnetism" is only an aspect of electric charge and currrent

You are randomly mixing up several things.

Electricity and Magnetism are inseparable. What we see as Magnetism is the manifestation of steady (unvarying) electric current. The unit of magnetic field (H) is 'Ampere-metre'.

Then RF signal is but a varying electromagnetic field, expressible in 'frequency'. Signal signifies information riding piggy-back on a 'Carrier' wave (of some frequency).

AC is a varying electric current, varying at a frequency. If it is unvarying (zero frequency; 0 Hz) it is called DC (Direct Current) like that of a battery.

As Magnetism has no frequency, Earths magnetic frequency has no meaning.

Magnetic field strength H, may be constant, varying, stronger or weaker depending on how it is produced and its purpose. In an EM wave H is the RMS value of a steadily varying field of constant frequency. Along with its dual E, Electric Field, it constitutes an EM wave.

The ratio (square root)

Eta = √[E/H]

determines whether it manifests as E or H. It (Eta) is called 'Intrinsic Impedance'.

electricity and magnetism go hand in hand. Both are fields and are the same phenomena really. So an rf signal will have an rf electric field and an rf magnetic field. Similarly a dc signal will have dc elec field and dc magnetic field. earth's mag field ahs all freq componants from dc up to some cut off freq (prob plasma freq?). but the magnitude at any partic freq changes vastly. dc is by far the greatest then low frequencies....

If you vary the field regularly then it has a frequency. If it varies randomly then it won't have a defined frequency. It's the same thing as sound.

No, magnetism does not have a frequency and neither does DC.

Yes, as part of an oscillating electromagnetic field.

No