I'm trying to make a setup for stage performances which will have singing/poetry/stand up comedy etc. I need suggestion on what all equipments will I need from scratch ? e.g., mic, speakers, the thing which sends mic i/p to speakers (what is that called?), amplifier (what's the use if needed). I just need the names of equipments, I'll try finding the brand within my budget on my own.
The chain will start with a mic. Usually in this situation a dynamic mic, which will withstand being dropped, knocked over - basically abused. To obviate this, a decent mic stand is a must. One that is difficult to knock over!
Next is a lead/cable, which will probably be connected to the next component via a Canon or XLR plug, rather than a jack plug.
Next comes a mixer, which has the propensity to attenuate the mic, and change the tone.
Amplifier is next, to boost the low signal to a level where it can feed the next.
Lastly are the speakers themselves, two being enough in a lot of gigs, and connected via a two core (usually) thicker cable via Speakon or jacks - or, occasionally, XLRs.
The mixer and amp are sometimes found in the same box - unsurprisingly called a 'mixer-amp'.
Tripod stands are useful for raising the speakers above the heads of the audience, to spread the sound better.
Some performers prefer to hear themselves better, by way of monitors, or foldback, which incurs use of another amp and extra speakers, which face the performer/s. Although with judicious placing of the speakers on the stage or performance area, aren't always necessary.
For extra homework, Google P.A., or public address system.
EDIT: thanks to Timinycricket - there also exists a beast called a powered speaker, which, as the name suggests, needs to be plugged in to the mains. It belongs in the line at the end - the mixer is plugged directly into it, as it contains a power amp and a speaker. Downside is that each (if there's more than one) will need both a lead from the mixer, and a power lead. This is doubly awkward with more than one, as extra leads have to be available.
I would never endeavor to advertise a particular brand, but many companies offer a complete PA System package (Public Address system, which is your multi-channel amplifier, speakers, speaker cables) along with microphones, mic stands, etc.
Just check any of the popular guitar or music supply websites for great package deals. And I'll recommend that you purchase at least one quality music stand, so that each performer has a place to set their sheet music, chord charts, poetry, or notes.