I have these two types of resistors available. Brown one i received from Arduino startup kit and the blue one i ordered online. I have a question if the type of both resistors are same.
Can you i use the blue one instead of brown one in my projects if the value is same.
Thanks
Regards/Farrukh
Color isn't really important. The actual value in ohms and wattage are. They both look to be 1/4w. I have some of those blue ones I think the tolerance is 1% or 2% but I can never read the darn stripes! Both should work fine for most UNO projects.
I worked for resistor manufacturing. Blue normally "metal film resistor" - tolerance less than 1%; beige-coloured are "carbon film" resistors - tolerance 5%; green or white are wire-wound resistors; Some manufacturers use beige-coloured body for "Standard Film" resistors. SFR are nothing but degraded MFRs. Fark brown, I am not sure but may be low TCR resistors.
thanks for the detailed answer. Metal film means i need to be careful when soldering to circuit because then it must not touch the board.
No, the metal film is inside. No worries. Usually, I think metal film resistors are the better choice, as they tend to be more accurate, also more temperature stable AFAIR.
One reason for carbon resistors can be failure behavior. AFAIK, carbon resistors damage does not decrease resistance but rather fail open, while decrease can happen in metal film. But that should not concern you for most Arduino use cases.
Carbon resistors are noisy, and deteriorate over time, but for most uses you would not care or notice,
personally resistors are so cheap I just get metal film and metal oxide types, but that's because I can
rather than need to.
The colour bands are much harder to distinquish on a blue background I find, I wish they were white.
MarkT:
I wish they were white.
White only comes in one shade. As a result reading a "9" band would be a bit of a challenge
Ah, that is a rather good point - white was a bad choice in the first place for a band colour, but is at
least visible against beige.
Orange, red and brown are easily confused against a blue background. SMT resistors get it right,
print the digits white on a black background, easy to read (with magnification, that is).
When the colour codes were developed components were big , if not huge, and even a "blind" user could easily read them. Now, with exceedingly small components such as 1/8w or smaller metal film resistors reading individual colours is more of a challenge.
White only comes in one shade. As a result reading a "9" band would be a bit of a challenge
I remember in the old valve days the body was white and unpainted. The colour for 9 ( white ) was quite easy to spot because it was paint. Most resistors were half watt at the smallest.
I remember in the old valve days the body was white and unpainted. The colour for 9 ( white ) was quite easy to spot because it was paint. Most resistors were half watt at the smallest.
I used to take apart old valve tv's to get components, and you are right. But the resistors ( generally 20% ) had often drifted over the years, and it was wise to measure them before use...
Allan
MarkT:
Orange, red and brown are easily confused against a blue background.
I find the colours on modern metal film resistors generally pretty easy to differentiate.
I know what you mean about brown/orange and orange/red though. At times when I've had to go through some very old stock resistors I've sometimes needed to measure a few of them with is ohmmeter just to "calibrate" my eye to what colour is what. It's like, er, ok, so that's what red looks like on these puppies. 
I use a DMM.. :o :o :o :o :o :o :o :o