2.4 is a stable release. but they are still keep improving it, so there are 2.4.21 and 2.4.22. usually they fix problems in 21 and add some functionalities. then become 2.4.22
2.5 is a develop release. then people can modify it freely and more actively, although the code have some fancy goodies. the code may be unstable. if some functionalities is show to be useful in 2.5.x , it will be kept, else be removed.
2.6 will be the new stable release, but it is still in test stage.
the difference between 2.4 and 2.6 is the architecture and many key components can be different, so can not keep using a 2.4.z version.
just like u have win 98, win 98 se and win98 service pack. but if the change is so huge, u get win2k and winxp.
yes, i think so. stay at a same job everyday will eventually lay you down.
so sometime i think my life is so boring. i stay at schools for 21 years, without touching the society seriously. maybe i should spend some time out of university before my further education.
fix machines? i did that all the time when i was in hust. install thirty machines os, software.. change hd, cdrom,... in one afternoon is a piece of cake for me.