This happens to be one of the programs for which I happen to use usually whenever I log on the computer, to of course use it to do everyday tasks. And it's for a reason: WinRAR, as popular as it is among users who perform tasks such as extracting and archiving, is simply the only program you'll ever need to get those split parts into one file. With the supporting of many, many formats such as ISO, ZIP, and ACE for unpacking purposes, WinRAR, without a doubt, takes the title of the absolute best file compressor there is out there available - let alone, so far, as "extreme" as this may sound - ever.
I've been using this ever since I had to unpack several files on one particular evening, whilst not having any sense of what the program is and what's the purpose of extraction. Of course, shortly thereafter I would gain some of that sense and ever since that day, I haven't stopped using it, given the reliability of it, in a sense that you'll know that it won't screw up on you and give you unwanted messages concerning file extraction. Not only that, it scans the files in order to keep your computer running smooth and clean by preventing any potential viruses that may come with whichever archive you're dealing with. Along with that is password protection, which is ultra-convenient especially if you happen to deal with confidential files or private files that you wouldn't want anyone to access (or whatever the case may be - either that or just for fun, I suppose!) from time to time, or on a regular basis. WinZIP, one of the other well-known programs that perform tasks along these lines, ironically enough, happened to be the first program I tried using in order to extract and unpack files into folders, all accordingly. Boy, did it ever give me a hassle-filled week (keep in mind that this was the very first program that I had ever used that deals with file compression), and in the end, I came out learning absolutely nothing, which was a shame since I found many users to be happy with the performance of WinZIP (which was then). Trouble after trouble, all doing the required steps as should, all to no avail. And that's when I immediately switched over to WinRAR, gave it a try, and in no time, WinZIP would simply be a mere thing of the past.
With a very small filesize that is bound to hardly take any space in regards to the RAM (Random Access Memory - in case you aren't aware, it mainly goes into account for multi-tasking purposes, such that the higher you have installed on your computer, the more open programs you're able to have before the point of freezing or computer performance inconvenience arrives). Simple, yet super-efficient and for those who are new to file compression, there's no reason to worry about spending needless time on reading material - and to say that it "gets the job done" would be more than an understatement.