Pop is the largest category in this directory by a wide margin, and that is a problem as much as a fact: "pop" is the label a station reaches for when it does not want to be pinned down. In practice the pop streams here divide into three quite different things, and knowing which one you are about to press play on saves a lot of skipping.
The first is current-chart radio, a tight rotation of perhaps forty songs repeated through the day, usually attached to a commercial broadcaster with presenters, traffic and advertising. It is designed to be joined at any moment and left at any moment. The second is catalogue pop, which plays hits across several decades with no particular era loyalty; these are usually automated, unpresented, and far deeper in rotation, so you will hear a song once and not again for hours. The third is national pop that happens to be sung in the local language, German Schlager, French chanson-pop, Italian and Brazilian chart music, which sits under the same genre tag but sounds nothing like an English-language chart station.
If you are browsing from outside the country a station broadcasts from, the third group is the interesting one. Chart pop has converged internationally to the point where a Top 40 station in three different countries will play substantially the same records. National-language pop has not converged at all, and it is where the surprises are.
On quality: most pop streams here run 128 kbps MP3, which is the format's workhorse setting and perfectly adequate on phone speakers or earbuds. Modern pop production is heavily compressed and loud before it ever reaches the encoder, so it survives low bitrates better than almost any other genre. If you are listening on a metered connection, a pop station is a reasonable place to accept a 64 kbps AAC+ feed.
