You don't want an in-depth explanation and if you don't know what they mean I wouldn't worry in the least about subjective and objective.
You say you know first, second, and third person POV and all you seem to be stuck on is the difference between Third Person Limited and Omniscient POV.
In simple terms Third Person Limited means the POV camera- through which the story is to be related and perceived by the reader- is placed on the shoulder of the chosen POV character and only what is seen or experienced through the camera (ie., known or sensed through the senses of the character) is narrated by the narrator - you.
You are the narrator- not the POV character- and you are simply linking everything together so the reader can understand what is happening, who is speaking and who is doing what.
Done well, it creates an illusion to the reader that he is experiencing the unfolding tale as if he were the POV character. You, as narrator, refrain from explaining things and keep a low profile, allowing the reader to interpret for himself what he is reading and why the POV character is doing this or that.
It is 'Limited' only to the extent that for any given scene or chapter (or for the whole novel if you wish) the POV is 'limited' to that of the chosen POV character.
If you wish to switch the camera to convey the POV of another character then that change of POV must be crystal clear to the reader- usually by hash symbols and line-spaces or a change of scene or a new chapter. If the reader is jolted unannounced from POV character to POV character it becomes head-hopping, dizzying and confusing.
Omniscient POV is where the narrator is a God-like all-knowing figure. The POV is his throughout with the POV camera positioned up above everything even though from time to time the omniscient narrator may zoom in on any particular event or character. Zooming in and out (or focusing in and out if you wish) in omniscient may give the illusion that the POV has switched to that character that has been focused upon but the POV does not move. The POV remains that of the Omniscient narrator who never needs to 'go into the head' of any character because he already knows what is there and simply has to convey that to the reader.
It seems to be the simplest of POV's but it is most definitely not the easiest because the temptation is to ramble on explaining everything about everybody simply because one can.
Good luck. The above is all you need to know- the rest will come through reading to see how others handle POV in their stories, and from your own experience.