[Triac help]

One more thing:
I plan to use the last ciricuit above. What wattage resistors should I use, and what should R_in's value be?

[Triac help]

Thank you.

[Shift Registers]

I will be attempting to make a LED sign, but first I need to do some research. My first question is:
What is a shift register, and how does it work?

[Triac help]

Like so?
This will work without much problem, running a lightbulb? The tungsten filiment is coiled, does that make it an inductive load?
Thank you for pointing me to this solution, though.

[detailed matter of ICs]

If you type in the name of the chip and then "datasheet" you'll get:
http://www.fairchildsemi.com/ds/NE/NE555.pdf
http://www.national.com/ds.cgi/LM/LM341.pdf
http://www.jameco.com/wcsstore/Jameco/Products/ProdDS/44581.pdf
http://www.daisy-laser.com/products/CD/handset/handset1/irreceiv.pdf

[Triac help]

Thank you. I ordered three MOC3041s. Just to be sure, the MOC3041 controls the triac, right?

[Triac help]

I am trying to use a triac to replace a broken relay in a circuit I made. A 555 is setup to flash on and off about every second. The positive pulses go to a relay, which controls a 60W 120VAC light bulb. I have bought a triac to replace the relay, but I don't exactly know how to use it.
Relay:
Coil: SPST 12 volt, 20mA, 250 ohm
Contacts 0.5A @ 125 VAC
Triac:
V_RRM: 300V
I_TRMS: 4A Max
I_GT(I & III) 30 mA Max
V_GT 2.5 V Max
I_H 30 mA Min

How can I use this triac?
P.S.
Do I need to heat sink it?