Since we have a thread about how people didn't know what Reboot was about before going to it, let me explain here and now:
~The biggest thing by far is that you CANNOT trade with other players under any circumstances.
~On that note, while you have access to the ability to share Use, Etc, and Setup items with your other characters in storage, you cannot share Equipment with your other characters. All equips MUST be earned on that character.
~On the regular worlds, Spell Traces are used to upgrade equipment, and players could give their equipment Bonus Potential, basically another few lines of slightly weaker potential. Various scrolls were also available to make achieving certain things, such as +10% chance for a scroll to work or the ability to preserve the equipment item if the scroll being used were to make it blow up. In Reboot, you have most none of that, only Star Force and Regular Potential.
~To make up for the above, all players have a beginner skill that increases Damage by 1% for every 2 levels that character has (Level 70 becomes 35% damage, Level 120 becomes 60%, etc)
~Cubes can be bought with Maplestory Mesos, albeit by amounts of about 12 mil and 21 mil for Red and Black cubes (respectively, with Blacks having a higher chance to rank up than Reds) Various other items in the Cash shop can also be bought with maplestory mesos, such as Miracle Circulators, Monster Park passes, and Hyper Teleport Rocks. All these items cost NX in the regular servers, thus leading people to call Reboot a free2play, free2win server versus other servers being largely pay2win.
~A lot of Regular Monsters are much stronger than their normal server counterparts on Reboot. Notable exceptions to this rule mostly pertain to monsters who do not exist in Korean Maplestory. These monsters also have higher EXP payouts as a result.
~The first time you play on reboot, on the first character you make, you will receive Reboot boxes that reward a good amount of maplestory 2 mesos, Reboot potions (1000 HP/MP recovered on use), and cubes, with a few other itmes thrown in for good measure.
~All new characters on reboot start with 200 Reboot potions and a box containing a Snail pet that lasts for 5 hours of total use (as opposed to x amount of time just existing like everything else in the game). I should let you know now, pets are pretty good for Reboot since you need to buy everything with maplestory mesos to get stronger, and picking everything up by hand gets tedious after a while, so if you want to think about spending some money on the game, consider getting a pet. All pets available in Reboot last 90 days and require a Water of Life (also purchasable with NX) to be available for another 90 days.
That is about everything I can think of you need to know about Reboot. If you need anymore help, well I'm sure this brain of mine can remember it after a few good knocks to the skull.
As for a good class to start with...
~F/P mage is a powerful mage with a number of Damage over Time options at their disposal, including poison clouds and little poisonous slime things.
~Evan is, in my opinion, an even more powerful mage if utilized correctly. With assistance from the dragon partner Mir, damage can be racked up without you even realizing just how much damage you are actually doing.
~Aran is powerful, but IMO she isn't "powerful" powerful until you achieve Adrenaline Boost at 1000 combo, at which point nothing is alive anymore. Don't be daunted by the large number, you get combo based on the number of hits a single attack does (Smash Swing deals 2 hits, so +2 combo).
I like Kinesis and Evan myself. Kinesis is probably a lot tougher to use than other classes due to the large number of short duration skills that require constant reactivation, but he is rewarding if you put in the effort to keep that all up.