You may have your difficulty set to Peaceful. Monsters will not spawn in Peaceful mode.
No, there are no creeper spawners naturally. Additionally, monster spawners will not spawn endermen or passive mobs (i.e. pigs, chickens, cows, etc.). You can although, download something such as not enough items, to obtain one.
If the difficulty isn't set to peaceful, mobs will spawn in creative mode.
Chickens, cows, sheep, wolves, and pigs will spawn on well lit grass in the Overworld. (Not the nether or the end.) Mooshrooms will spawn on Mycelium in the Overworld, Skeletons, creepers, spiders, bats, and zombies spawn in dark places. (Only in the Overworld.) Zombie pigmen and ghasts spawn randomly in the nether. Skeletons, and wither skeletons spawn in nether fortresses, and blazes spawn only near blaze spawners. (Found in nether fortresses.) Ocelots spawn in jungles, and squids spawn underwater in the Overworld. Endermen spawn rarely in dark places in the Overworld, or witha much higher frequency in the end. Cave spiders spawn from spawners found in abondoned mineshafts. Villagers spawn when the map is created and when other villagers breed and have babies. Slimes spawn at low elevations in slime chunks or in swamps. Silverfish spawn from their spawners in one of the worlds three(or less) strongholds. Witches spawn in witch huts when the map is created. One ender dragon spawns in the end when the map is generated. Those are all the mobs which are created naturally, for more information, I advise you go tohttp://www.minecraftwiki.net/wiki/MobsIf all these conditions are fulfilled, and no mobs are spawning, I suggest you press Esc and change your difficulty to easy, medium, or hard, as no monsters spawn while you are in peaceful mode.In creative mode you can also use Spawner Eggs (found in your inventory) to spawn mobs
Yes, apparently, they will teleport into your home. It has happened before, trust me- I'm in peaceful mode right now... and guess who's also there. The enderman. So yes, they do spawn in peaceful mode.
Yes. If you switch to peaceful, monster spawners will stay there, but they won't spawn any monsters.
You can spawn anything that you can get in-game plus a few other things such as sponge and monster-spawners and bedrock.
Peaceful mode means that no monsters spawn, so there will be no Slimes.
You may have your difficulty set to Peaceful. Monsters will not spawn in Peaceful mode.
No, there are no creeper spawners naturally. Additionally, monster spawners will not spawn endermen or passive mobs (i.e. pigs, chickens, cows, etc.). You can although, download something such as not enough items, to obtain one.
open server.properties with notepad word ect and change spawn-monsters=true to spawn-monsters=false.
Mob spawners generate naturally in dungeons, strongholds and abandoned mine-shafts. Dungeon spawners can be either; Zombie, Skeleton or Spider. Stronghold spawners will spawn only silverfish and mineshaft spawners spawn only cave spiders. There are mods you can install to change what spawns in a spawner or to be able to pick a spawner up. You can also place spawners in creative mode, but they will only spawn pigs.
If the difficulty isn't set to peaceful, mobs will spawn in creative mode.
As glowstone gives off light, the only monster than can spawn on it is a slime at the bottom of the map.
by using spawn eggs or mob spawners with a mob in them
No, there are preset spawners undrground and hidden ones in blocks.
Chickens, cows, sheep, wolves, and pigs will spawn on well lit grass in the Overworld. (Not the nether or the end.) Mooshrooms will spawn on Mycelium in the Overworld, Skeletons, creepers, spiders, bats, and zombies spawn in dark places. (Only in the Overworld.) Zombie pigmen and ghasts spawn randomly in the nether. Skeletons, and wither skeletons spawn in nether fortresses, and blazes spawn only near blaze spawners. (Found in nether fortresses.) Ocelots spawn in jungles, and squids spawn underwater in the Overworld. Endermen spawn rarely in dark places in the Overworld, or witha much higher frequency in the end. Cave spiders spawn from spawners found in abondoned mineshafts. Villagers spawn when the map is created and when other villagers breed and have babies. Slimes spawn at low elevations in slime chunks or in swamps. Silverfish spawn from their spawners in one of the worlds three(or less) strongholds. Witches spawn in witch huts when the map is created. One ender dragon spawns in the end when the map is generated. Those are all the mobs which are created naturally, for more information, I advise you go tohttp://www.minecraftwiki.net/wiki/MobsIf all these conditions are fulfilled, and no mobs are spawning, I suggest you press Esc and change your difficulty to easy, medium, or hard, as no monsters spawn while you are in peaceful mode.In creative mode you can also use Spawner Eggs (found in your inventory) to spawn mobs